Patent Publication Number: US-7712862-B1

Title: Ink stalagmite detection

Description:
BACKGROUND 
     Ink jet printing devices and processes use a multitude of controlled ink discharge nozzles in order to form images on print media. In some devices, automated testing procedures are performed to determine which, if any, of the ink discharge nozzles are failing to operate properly. Such testing procedures are referred to as “drop detection”. Subsequent printing operations can be automatically modified, if needed, in the interest of mage quality once any failed nozzles are identified. 
     Waste ink is generated during each drop detection procedure. Over the course of numerous such tests, waste ink can accumulate and harden in the form of “stalagmites”. Such stalagmites are typically supported by a waste ink receptacle (i.e., spittoon) and can grow until they interfere with the operation of the drop detection sensors (i.e., drop detectors). Such interference with the drop detectors can lead to false interpretation of massive nozzle failures, automatically rendering the ink jet printing device inoperative until serviced by personnel. 
     Accordingly, the embodiments described hereinafter were developed in the interest of addressing the foregoing problems. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present embodiments will now be described, by way of example, with reference to the accompanying drawings, in which: 
         FIG. 1  depicts a block diagrammatic view of select portions of a printing apparatus according to one embodiment; 
         FIG. 2  depicts a block diagrammatic view of select portions of the printing apparatus of  FIG. 1 ; 
         FIG. 3  depicts a diagrammatic perspective view of the printing apparatus of  FIG. 1  according to one operating state; 
         FIG. 4  depicts a diagrammatic perspective view of the printing apparatus of  FIG. 1  according to another operating state; 
         FIG. 5  depicts a block schematic view of a network printer according to another embodiment; 
         FIG. 6  depicts a flow diagram of a method according to still another embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Introduction 
     Means and methods for detecting stalagmites formed of waste ink media are provided by the present teachings. A spittoon of an ink jetting printer is shifted toward one or more drop detectors. Light-beam and/or other detection means of the drop detectors sense the presence of any ink stalagmites that are supported on the spittoon. A warning message indicative of stalagmite detection is generated and dispatched. Additionally, or in the alternative, a record of the stalagmite detection event is recorded within computer-accessible storage media of the printer for later recall. Such detection typically allows sufficient lead time to remove the stalagmite(s) during routine servicing and before automated shutdown of the printer is performed. 
     In one embodiment, an apparatus includes a drop detector that is configured to detect an emission of an ink media from one or more of ink jetting devices. The apparatus also includes a spittoon configured to receive ink media emitted from the one or more ink jetting devices. The drop detector is also configured to provide a detection signal in response to detecting at least one ink media stalagmite supported by the spittoon. 
     In another embodiment, a method includes shifting a spittoon toward a drop detector. The method also includes detecting at least one ink stalagmite supported by the spittoon using the drop detector. The detecting is performed while the spittoon is shifted toward the drop detector. The at least one stalagmite includes waste ink media. The method additionally includes issuing a signal indicative of detecting the at least one ink stalagmite from the drop detector. 
     In yet another embodiment, a controller for an ink jetting printer is provided. The controller is configured to issue a command signal to cause a spittoon to be shifted toward a drop detector. The controller is also configured to receive a detection signal from the drop detector indicative of one or more ink stalagmites supported by the spittoon. The controller is further configured to issue a warning message in response to the receiving the detection signal. 
     First Illustrative Embodiment 
       FIG. 1  depicts a block diagrammatic view of select portions of a printing apparatus (printer)  100  according to one embodiment. The printer  100  is illustrative and non-limiting in nature. Thus, other printers can be defined, configured and used in accordance with the present teachings. 
     The printer  100  includes a page-wide print array  102 . The print array  102  includes a plurality of dies  104 . The dies  104  are arranged in staggered, partially overlapping adjacency with one another such that a continuous printable width “W” is defined by the array  102 . Each die  104  includes a plurality of ink discharge nozzles (not shown) configured to discharge liquid ink so as to form images on print media (not shown) in response to corresponding control signaling. One having ordinary skill in the printing and related arts can appreciate the typical characteristics and operations involved in ink jet printing, and further elaboration of the print array  102  is not required for purposes of understanding the present teachings. 
     The printer  100  also includes a service station  106 . The service station  106  is configured and equipped so as to be moved (translated) from a location away from the print array  102  along a path beneath the print array  102 . The bidirectional arrow labeled “D” indicates the translational nature of the service station  106 . In this way, the service station  106  can perform drop detection testing and nozzle cleaning of the print array  102 . Further description of typical service station  106  operations is provided hereinafter. 
     The service station  106  includes a web-wipe assembly  108 . The web-wipe assembly  108  is configured to make wiping, cleaning contact with the print array  102  so as to remove residual ink, media dust and/or other debris there from. The service station  106  also includes a spittoon (waste ink receptacle)  110 . The spittoon  110  typically, but not necessarily, includes a sponge or foam-like material configured to receive waste ink that is produced during drop detection procedures. As shown, an illustrative stalagmite  112 , comprised of waste ink, has formed upon and is supported by the spittoon  110 . 
     The service station  106  of the printer  100  also includes one or more drop detectors  114 . Only one drop detector  114  is depicted in  FIG. 1  for simplicity. Each drop detector  114  is configured to detect the emission of ink  116  from one or more nozzles of the dies  104  of the print array  102  during drop detection operations. In one embodiment, each drop detector  114  is configured to detect the emission of ink  116  by way of a light beam emitter and corresponding light sensor (i.e., emitter and sensor pair). Other embodiments having other detection means/schemes can also be used. The service station  106  further includes a print array cover  118  that can be selectively rotated toward and away from the print array  102  so to provide a protective capping of the dies  104  when printing operation are not being performed. 
     Typical drop detection operations are performed as follows: the service station  106  is moved into position generally beneath one end of the print array  102 . Ink discharge nozzles are controllably operated (i.e., “fired”) one at a time while the corresponding drop detector(s)  114  is/are located in detection proximity there to. Ink discharge detection signals are provided accordingly by the drop detector(s)  114 . The service station  106  is translated beneath the print array  102  while the ink discharge nozzles are individually and progressively test fired, until all of the nozzles of the print array  102  have been tested by way of the drop detector(s)  114 . The resulting detection signals (or lack thereof) are used to identify which, if any, ink discharge nozzles faded to operate and subsequent printing operations are controlled accordingly. 
       FIG. 2  depicts a block diagrammatic view of select portions of the printer  100  introduced above. As depicted, the service station  106  is located away from the print array  102 . The web-wipe assembly  108  has been rotated about an axis  120  so as to shift (i.e., elevate) the spittoon  110  toward the one or more drop detectors  114 . In this way, the illustrative stalagmite  112  is also shifted closer to the detection beam (or other means) of one of the drop detectors  114 . If the stalagmite  112  is of sufficient size (i.e., height), then the corresponding drop detector  114  will detect the stalagmite  112  and provide a corresponding signal. Further elaboration regarding stalagmite detection and signal procedures according to the present teachings is provided hereinafter. 
       FIG. 3  a block diagrammatic view of select portions of the illustrative and non-limiting printer  100  as introduced above. The printer  100  includes three drop detectors  114  supported by a circuit card  122 . Each drop detector  114  is configured to detect ink emissions by way of a light beam  124 . It is to be noted that each light beam  124  can be defined by an emission in the visible, infrared or ultraviolet range of the electromagnetic spectrum. The spittoon  110 , as introduced above, is shown as a generally elongated block of sponge-like material located in spaced adjacency to the drop detectors  114 . Such spaced adjacency (i.e., generally apart or away from) is typical during drop detection procedures so that waste ink (overspray) is collected by the spittoon  110 . The spittoon  110  supports two illustrative stalagmites (also referred to as ink stalagmites or waste ink stalagmites)  112  that have progressively formed on the spittoon  110  as a result of successive drop detection testing. 
       FIG. 4  a block diagrammatic view of select portions of the illustrative and non-limiting printer  100  as introduced above and as further described with respect to  FIG. 3 . As shown in  FIG. 4 , the spittoon  110  as been shifted toward (i.e., proximate to) the drop detectors  114  as indicated by the arrow “D 1 ”. The shifting of the spittoon  110  results in at least one of the illustrative stalagmites  112  preventing the light beam  124 A from reaching the sensor  126  of the drop detector  114 A. The drop detector  114 A will provide a corresponding signal indicative of the stalagmite  112  detection. 
     It is noted that the spittoon  110  is assumed to be shifted by way of angular motion of the supporting web-wipe assembly (see  FIG. 2 ). In another embodiment, other means can be used to positionally shift the spittoon  110  relative to the drop detectors  114 . In another non-limiting and illustrative embodiment, the spittoon is essentially stationary with respect to some supporting structure and the drop detector(s) is/are moved relative thereto. Once the stalagmite detection and signaling process is complete, the spittoon  110  and the drop detectors  114  are returned to the spaced adjacency shown in  FIG. 3 . 
     Second Illustrative Embodiment 
     Reference is now made to  FIG. 5 , which depicts at network printer  200  according to another embodiment of the present teachings. The printer  200  is illustrative and non-limiting in nature. Thus, other printers can be defined, configured and used in accordance with the present teachings. 
     The printer  200  includes a controller  202 . The controller  202  is configured to control various normal operations of the printer  200 . As such, the controller  202  can include and/or be defined by one or more microprocessors or microcontrollers, one or more application-specific integrated circuits (ASICs), a state machine, digital circuitry, analog circuitry, etc. Other means can be used to define the controller  202 . For purposes of non-limiting example, it is assumed that the controller  202  includes at least one microprocessor configured to control operations of the printer  200  in accordance with a program code. The controller  202  is connected in control signal and/or data communication with various other means and resources of the printer  200 . 
     The printer  200  also includes a print array  204 . The print array  204  includes numerous, individually controlled ink discharge nozzles configured to form images on media  206 . The print array  204  is understood to be a page-wide print array. The print array  204  is coupled so as to be controlled by the controller  202 . 
     The printer  200  also includes a service station  208 . The service station  208  includes a spittoon  210  and at least one drop detector  212 . As depicted, an ink stalagmite  214  has formed on and is supported by the spittoon  210 . The service station  208  is configured to perform various operations including, for non-limiting example, drop detection during testing of the print array  204 . 
     The printer  200  also includes storage media  216 . The storage media  216  can be defined by any one or more tangible, computer-readable (i.e., readable and/or writable) storage media. Non-limiting examples of storage media  216  include optical storage media, magnetic storage media, solid-state memory, non-volatile solid-state memory, etc., alone or in any suitable combination. Other forms of storage media  216  can also be used. The storage media  216  is configured to provide one or more program code segments to controller  202 . The storage media  216  is also configured to store information recorded by the controller  202 . 
     The printer  200  further includes other resources  218 . Such other resources  218  can include any means as desired or required to support normal printer operations. Non-limiting examples of other resources  218  include a power supplies, print media transport mechanisms, a print media dryer, an operator interface, communication input/output circuitry, wireless communication resources, post-imaging media treatment devices, one or more reservoirs of color ink media, etc. One having ordinary skill in the printing arts can appreciate that the printer  200  can include various means and resources typical to inkjet imaging operations, and that an exhaustive description is not needed for purposes of understanding the present teachings. 
       FIG. 5  further depicts additional illustrative and non-limiting network resources. Specifically depicted are a user computer  220  and a server  222  coupled in communication with each other and the printer  200  by way of a local area network (LAN)  224 . The local area network  224  is also coupled in communication with the Internet  226  by way of a router  228 . Illustrative operations of the printer  200  are described hereinafter. 
     First Illustrative Method 
       FIG. 6  is a flow diagram depicting a method according to one embodiment of the invention. The method of  FIG. 6  includes particular operations and order of execution. However, other methods including other operations, omitting one or more of the depicted operations, and/or proceeding in other orders of execution can also be used according to the present teachings. Thus, the method of  FIG. 6  is illustrative and non-limiting in nature. The method of  FIG. 6  is described with reference to  FIG. 5  in the interest of understanding the present teachings. 
     At  300 , a controller of an ink jetting (i.e., inkjet) printer issues a drop detection command to a service station and/or other resources there of. For purposes of non-limiting example, it is assumed that the controller  202  provides one or more signals that cause the service station  208  to perform a drop detection sequence. 
     At  302 , a waste ink receiving spittoon of the ink jetting printer is shifted toward one or more drop detectors of the printer. For purposes of the ongoing example, the service station  208  shifts the spittoon  210  toward the drop detector  212 . 
     At  304 , the one or more drop detectors are used to detect the presence of any waste ink stalagmites supported by the spittoon. If no stalagmites are detected, then the method proceeds on  308  below. If one or more stalagmites are detected by the drop detector(s), then the method proceeds to  306  below. For purposes of the ongoing example, it is assumed that the drop detector  212  detects the stalagmite  214  and sends a corresponding detection signal to the controller  202 . Under this example, the method proceeds to  306  below. 
     At  306 , a warning message is issued indicative of the stalagmite detection at  304  above. Such a message can be provided locally at the printer by way of a user interface, can include a message transmitted to a user by way of a network, and/or by way of other messaging schemes. The message and/or related data (e.g., detection time and date, specific drop detector(s) sensing the stalagmite, etc.) can also be recorded on computer-accessible storage media for later access. For purposes of the ongoing example, it is assumed that the controller  202  issues a warning message to a remote recipient by way of the Internet  226 , and records the stalagmite detection event on the storage media  216 . 
     At  308 , the spittoon is shifted away from the one or more drop detectors of the printer. For purposes of the ongoing example, it is assumed that the service station  208  shifts the spittoon  210  away from the drop detector  212 . The spittoon  210  is now in position to receive waste ink media during normal drop detection operations. 
     At  310 , the drop detection procedure continues as defined for the printer. Such procedure typically includes sequentially test firing each of the ink jetting nozzles while the corresponding drop detector(s) are in sensing proximity thereto. The overall results of the drop detection testing are then automatically analyzed and subsequent printing operations are controlled accordingly. For purposes of the ongoing example, it is assumed that once the drop detection sequence is completed, the service station  208  moves away from the print array  204  and normal printing operations can then be performed. 
     The foregoing method is illustrative of any number of methods contemplated by the present teachings, wherein detection of one or more stalagmites is used to trigger issuance of a warning message to a user. The appropriate service personnel or a skilled user can then address the matter by removing the stalagmites from the supporting spittoon. In this way, normal operations of the corresponding printer can be performed without interruption due to false nozzle failure interpretation caused by stalagmite growth into the drop detection zone. 
     In one embodiment, the automated stalagmite detection taught herein provides approximately three to four weeks of advance warning before false perception of massive nozzle outages causes automatic printer shutdown. Other advance lead times can also be achieved. Such advance warning can allow for removal of the stalagmites during a routine and otherwise necessary maintenance call for replenishment of printer consumables (e.g., paper media, ink media, etc.). Furthermore, access to stalagmite detection records kept within the storage media of the printer can alert a service technician or other user to the need to remove ink stalagmites before automated printer shutdown is performed. 
     In general, the foregoing description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the invention should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In sum, it should be understood that the invention is capable of modification and variation and is limited only by the following claims.