Abstract:
In one embodiment, a latch for a liquid dispensing component includes: a first part for holding a liquid dispensing component in a seated position in a holder, the first part movable between an open position in which the component may be installed in or removed from the holder and a closed position in which the component is held in the seated position in the holder; and a second part for connecting the component to a liquid supply port, the second part movable, while the first part is in the closed position, between a disconnected position in which the component is not connected to the liquid supply port and a connected position in which the component is connected to the liquid supply port.

Description:
BACKGROUND 
       [0001]    In some inkjet printers, ink is supplied to a multi-color printhead module through multiple needle-septum connections in which each needle is inserted through a corresponding septum. Each color of ink requires a separate needle-septum connection. Consequently, the force needed to simultaneously insert the needles into the septa to make multiple ink connections, or to withdraw the needles simultaneously from the septa to break the connections, increases as the number of ink colors increases—the more colors the printhead uses, the greater the force needed to make and break the ink supply connections. Unfortunately, as this force increases, so too does the risk of dislodging the printhead module from its seated, properly aligned position in the printer carriage during needle insertion and needle withdrawal. Keeping the printhead module properly aligned helps the user accurately and safely make and break the ink connections. 
     
    
     
       DRAWINGS 
         [0002]      FIG. 1  is a block diagram illustrating one example of an inkjet printer in which embodiments of the new latching solution may be implemented. 
           [0003]      FIGS. 2-4  are perspective views illustrating one embodiment of a new latch for securing a printhead module in a printer carriage, for example in a printer such as that shown in  FIG. 1 . In the embodiment of  FIGS. 2-4 , the hold down and engagement functions are achieved using separate actuators in a dual latching operation. The latch is fully open in  FIGS. 2 and 3 . The latch is fully closed in  FIG. 4 . 
           [0004]      FIG. 5  is a detail view illustrating one part of the latch of  FIGS. 2-4  for holding the printhead module. 
           [0005]      FIG. 6  is a detail view illustrating another part of the latch of  FIGS. 2-4  for connecting the ink supply ports to the printhead module. 
           [0006]      FIGS. 7-13  are elevation views illustrating a sequence of operation for the latch of  FIGS. 2-4 . 
           [0007]      FIGS. 11A ,  11 B,  12 A,  12 B, and  13 A,  13 B are detail views taken from  FIGS. 11 ,  12  and  13 , respectively. The ink supply ports are omitted in  FIGS. 11A ,  12 A, and  13 A to better illustrate some of the latch parts. Some of the latch parts are omitted in  FIGS. 11B ,  12 B, and  13 B to better illustrate movement of the ink supply ports. 
           [0008]      FIGS. 14-16  are perspective views illustrating another embodiment of a new latch for securing a printhead module in a printer carriage. In the embodiment of  FIGS. 14-16 , the hold down and engagement functions are achieved using one actuator in a single latching operation. The latch is fully open in  FIGS. 14 and 15 . The latch is fully closed in  FIG. 16 . 
           [0009]      FIG. 17  is a detail view illustrating one part of the latch of  FIGS. 14-16  for holding the printhead module. 
           [0010]      FIG. 18  is a detail view illustrating another part of the latch of  FIGS. 14-16  for connecting the ink supply ports to the printhead module. 
           [0011]      FIGS. 19-23  are elevation views illustrating a sequence of operation for the latch of  FIGS. 14-16 . 
           [0012]      FIGS. 22A ,  22 B,  23 A, and  23 B are detail views taken from  FIGS. 22 and 23 , respectively. The ink supply ports are omitted in  FIGS. 22A and 23A  to better illustrate some of the latch parts. Some of the latch parts are omitted in  FIGS. 22B and 23B  to better illustrate movement of the ink supply ports. 
           [0013]      FIG. 24  is a section view taken along the line  24 - 24  in  FIG. 20 . 
           [0014]      FIG. 25  is a section view taken along the line  25 - 25  in  FIG. 21 . 
       
    
    
       [0015]    The same part numbers are used to designate the same or similar parts throughout the figures. 
       DESCRIPTION 
       [0016]    A new latching solution has been developed to help keep the printhead module properly aligned during needle insertion and needle withdrawal, thus allowing the user to accurately and safely make and break the ink connections. In one embodiment of the new latching solution, one part of the latch secures the printhead module in the properly aligned position while a second part of the latch moves the needles and septa together to make the ink connections (and moves the needles and septa apart to break the ink connections). In one example implementation, each function is achieved using independent levers in a dual latching operation. In another example implementation, both functions are achieved using interconnected levers in a single latching operation. 
         [0017]    Example embodiments of the invention are described below with reference to an inkjet printer in which a carriage scans a multi-color printhead module back and forth across the print media. However, embodiments are not limited to scanning inkjet printers or even inkjet printing in general. Embodiments might also be implemented in other types of inkjet printers or in other types of liquid dispensers. The embodiments shown in the figures and described below, therefore, illustrate but do not limit the invention, which is defined in the Claims following this Description. 
         [0018]    As used in this document, “liquid” means a fluid not composed primarily of a gas or gases. 
         [0019]      FIG. 1  is a block diagram illustrating one example of an inkjet printer  10  in which embodiments of the invention may be implemented. Referring to  FIG. 1 , printer  10  includes a carriage  12  carrying a printhead module  14 . Printhead module  14  includes a series of ink cartridges  16 ,  18 ,  20 ,  22 ,  24 , and  26  connected to a printhead  28 . Ink is supplied to cartridges  16 - 26  from a series of ink supplies  30 ,  32 ,  34 ,  36 ,  38 , and  40  located remote from carriage  12 . Each ink cartridge  16 - 26  represents generally the operative components needed to regulate the flow of ink to printhead  28 , for example, a single color of ink such as black (K), yellow (Y), cyan (C), magenta (M), light cyan (CL) and light magenta (ML). Each ink cartridge  16 - 26  may itself be a removable component in module  14  or a permanent component of module  14 . Printhead  28  represents generally the operative components needed to expel ink from module  14  on to print media  42 . For example, black ink is pumped or otherwise introduced into cartridge  16  from ink supply  30  to a pressure regulator chamber in cartridge  16 . Ink flows from the regulator chamber through a filter to printhead  28 , where it is ejected on to print media  42 . 
         [0020]    An inkjet printhead  28  is typically a small electromechanical assembly that contains an array of miniature thermal, piezoelectric or other devices that are energized or activated to eject small droplets of ink out of an associated array of nozzles. A typical thermal inkjet printhead, for example, includes a nozzle plate arrayed with ink ejection nozzles and firing resistors formed on an integrated circuit chip. Printhead  28  may be formed, for example, as a series of discrete printheads each serving one or more cartridges  16 - 26 , or as a single printhead serving all of cartridges  16 - 26  through multiple nozzle arrays and corresponding fluid delivery channels. 
         [0021]    A print media transport mechanism  44  advances print media  42  past carriage  12  and printhead  28 . For a movable, scanning carriage  12 , media transport  44  typically will advance media  42  incrementally past carriage  12 , stopping as each swath is printed and then advancing media  42  for printing the next swath. An electronic controller  46  is operatively connected to carriage  12 , ink cartridges  16 - 26 , printhead  28 , and media transport  44 . Controller  46  communicates with external devices through an input/output device  48 , including receiving print data for inkjet imaging. The presence of an input/output device  48  in  FIG. 1 , however, does not preclude the operation of printer  10  as a standalone unit. By coordinating the relative position of carriage  12  with media  42  and the ejection of ink drops, controller  46  produces the desired image on media  42 . 
       Dual Latching Embodiment 
       [0022]      FIGS. 2-4  are perspective views illustrating one embodiment of a new latch  50  for securing a printhead module  14  in a printer carriage  12 , for example in a printer  10  such as that shown in  FIG. 1 . In the embodiment of  FIGS. 2-4 , the module hold down and ink supply connecting functions are achieved using independent levers in a dual latching operation. Latch  50  is fully open in  FIGS. 2 and 3 . Latch  50  is fully closed in  FIG. 4 . Referring to  FIGS. 2-4 , latch  50  includes a first part  52  for holding printhead module  14  in the desired position seated in carriage  12  and a second part  54  for connecting printhead module  14  to ink supply ports  56 ,  58 ,  60 ,  62 ,  64 , and  66  while first part  52  holds printhead module  14  in the seated position in carriage  12 . 
         [0023]      FIG. 5  is a detail view illustrating latch part  52 . Referring to  FIGS. 2-5 , latch part  52  includes a first lever arm  68  connected to a pair of contact assemblies  70  spaced apart on opposite sides of printhead module  14 . Each contact assembly  70  includes a pivot arm  72 , a biasing spring  74 , and a contact surface  76  on arm  72  for engaging a corresponding contact surface  78  on printhead module  14 . 
         [0024]      FIG. 6  is a detail view illustrating latch part  54 . Referring to  FIGS. 2-4  and  6 , latch part  54  includes a second lever arm  80  operatively connected to ink supply ports  56 - 66  through a pair of connecting links  82  and a supply port mounting block  84 . Mounting block  84  supports ink supply ports  56 - 66  to allow all six ports to move together as a unit for connecting to and disconnecting from printhead module  14 . As best seen in  FIG. 6 , each ink supply port  56 - 66  includes a septum  86  facing a corresponding needle  88  ( FIGS. 3 and 7 ) of printhead module  14 . Needles  88  are protected by a shroud  90  along the top of printhead module  14 . 
         [0025]    The operation of latch  50  will now be described with reference to the elevation views of  FIGS. 7-13 . Different line types are used in  FIGS. 7-13  to help distinguish between overlapping parts. Throughout the figures, direction arrows  87  indicate the motion of first lever arm  68 , direction arrows  89  indicate the motion of second lever arm  80 , and direction arrows  91  indicate the motion of ink supply port mounting block  84 . 
         [0026]    Referring first to  FIG. 7 , printhead module  14  has been placed in carriage  12  but latch  50  remains fully open. The placement of printhead module  14  and the position latch  50  in  FIG. 7  corresponds to that shown in the perspective view of  FIG. 2 . Latch part  52  is operated first to hold printhead module  14  in the desired position during the subsequent operation of latch part  54 . As best seen by comparing  FIGS. 7 ,  8  and  9 , each pivot arm  72  rotates down (clockwise) with first lever arm  68  through a first range of motion until contact surfaces  76  engage corresponding contact surfaces  78  on printhead module  14  to push printhead module  14  into the seated position, properly aligned in carriage  12 . During this first part of the operation, first lever arm  68  pivots on a first pin  92  at a first location  94  in a first slot  96  in carriage  12 . Also during this first part of the operation, the motion of first lever arm  68  is guided by a second pin  98  moving along a second slot  100  in carriage  12 . 
         [0027]    Then, as first lever arm  68  is pushed further down (clockwise), first lever arm  68  pivots on second pin  98  at a second location  102  in second slot  100  through a second range of motion, as best seen by comparing  FIGS. 9 and 10 . Accordingly, pivot arm  72  pivots at contact surface  76 , compressing spring  74  to maintain pressure on printhead module  14  in the seated position in carriage  12  and to help retain latch part  52  in the fully closed position shown in FIG.  10 —the contact force on first lever arm  68  at surface  76  is offset from second pin  98  to exert a torque on lever arm  68  toward the closed position. During this part of the operation, motion of first lever arm  68  and arm  72  is guided by first pin  92  moving along slot  96  from first location  94  to a third location  104 . 
         [0028]    First lever arm  68  pivoting on first pin  92  through the first range of motion and then pivoting on second pin  98  through the second range of motion forms a first lever  69  for actuating first latch part  52  to move from the fully open position shown in  FIG. 7  to the partially closed position shown in  FIG. 9  and then to the fully closed position shown in  FIG. 10 . 
         [0029]    With latch part  52  closed and printhead module  14  seated, as shown in  FIG. 10 , each septum  86  on a corresponding ink supply port  56 - 66  is aligned with needle  88 . Latch part  54  may then be operated to connect printhead module  14  to ink ports  56 - 66  as described below with reference to  FIGS. 10-13 . Detail views  FIGS. 11A ,  11  B,  12 A,  12 B, and  13 A,  13 B are provided for clarity. Block  84  and supply ports  56 - 66  are omitted in  FIGS. 11A ,  12 A, and  13 A to better illustrate the latch parts. Some of the latch parts are omitted in  FIGS. 11  B,  12 B, and  13 B to better illustrate the movement of supply ports  56 - 66 . 
         [0030]    As best seen by comparing  FIGS. 10 ,  11  and  12 , second lever arm  80  is rotated down (counterclockwise) to move block  84  carrying ink supply ports  56 - 66  toward needles  88 . During this part of the operation, second lever arm  80  pivots on a third pin  106  at a fourth location  108  in a third slot  110  in carriage  12 . Connecting link  82  pivots on a fourth pin  112  on block  84  and a fifth pin  114  on second lever arm  80 . Thus, connecting link  82  converts the rotating motion of second lever arm  80  into a linear motion of block  84  carrying supply ports  56 - 66 . As shown in  FIG. 12 , when latch part  54  is fully closed each needle  88  pierces the corresponding supply port septum  86  to make the ink connections to printhead module  14  through supply ports  56 - 66 . 
         [0031]    Printhead module  14  is disconnected from ink supply ports  56 - 66  by opening latch part  54 . It is desirable to keep needles  88  and ink supply ports  56 - 66  aligned as needles  88  are withdrawn from supply ports  56 - 66  to minimize the necessary withdrawal force and, accordingly, to lower the risk of damaging needles  88  or septa  86 . Application of the withdrawal force tends to unseat printhead module  14  and misalign needles  88  in supply ports  56 - 66 . Thus, as best seen by comparing  FIGS. 12 and 13 , latch part  54  includes a blocking surface  116  that is extended to block printhead module  14  during disengagement, keeping printhead module  14  seated in carriage  12  and needles  88  correctly aligned with supply ports  56 - 66 . As second lever arm  80  moves up (clockwise) in  FIG. 13 , the friction of the withdrawing septa  86  on needles  88  causes third pivot pin  106  to slide toward the front of third slot  110  at a fifth location  118  and bring blocking surface  116  into contact with printhead module  14 . This contact area is designated by part number  120  in  FIG. 13 . Printhead module  14  becomes a temporary fulcrum for second lever arm  80  (bearing against printhead module  14  at contact area  120 ), simultaneously giving mechanical advantage to the disconnect force and blocking printhead module  14  from being unseated by that force. 
         [0032]    Once septa  86  are disconnected from needles  88 , a biasing spring (not shown) may be used to return third pivot pin  106  to the rear of third slot  110  at fourth location  108  shown in  FIG. 10 , or pin  106  may be allowed to return to fourth location  108  at the urging of the continued rotation of lever arm  80  as latch part  54  is moved to the fully open position ( FIG. 10 ) or as lever arm  80  is moved down in the next operation to close part  54  and reconnect printhead module  14  to ink supply ports  56 - 66 . 
         [0033]    Second lever arm  80  pivoting on third pin  106  forms a second lever  81  for actuating second latch part  54  to move between the fully open position shown in  FIG. 10  to the fully closed position shown in  FIG. 12 . 
       Single Latching Embodiment 
       [0034]      FIGS. 14-16  are perspective views illustrating another embodiment of a latch  50  for securing printhead module  14  in a printer carriage  12 . Latch  50  is fully open in  FIGS. 14 and 15 . Latch  50  is fully closed in  FIG. 16 . In this embodiment of latch  50 , the hold down and engagement functions are achieved using one actuator in a single latching operation. 
         [0035]    Referring to  FIGS. 14-16 , latch  50  includes a first part  52  for holding printhead module  14  in the desired position seated in carriage  12  and a second part  54  for connecting printhead module  14  to ink supply ports  56 ,  58 ,  60 ,  62 ,  64 , and  66  while first part  52  holds printhead module  14  in the desired position in carriage  12 . A single actuator  122  synchronizes the movement of each latch part  52 ,  54  for opening and closing latch  50 . 
         [0036]      FIG. 17  is a detail view illustrating latch first part  52  and actuator  122 . Referring to  FIGS. 14-17 , latch part  52  includes a first lever arm  68  connected to a pair of contact assemblies  70  spaced apart on opposite sides of printhead module  14 . Each contact assembly  70  includes a pivot arm  72 , a biasing spring  74 , and a contact surface  76  on arm  72  for engaging a corresponding contact surface  78  ( FIG. 14 ) on printhead module  14 . 
         [0037]      FIG. 18  is a detail view illustrating latch second part  54 . Referring to  FIGS. 14-16  and  18 , latch part  54  includes a second lever arm  80  operatively connected to ink supply ports  56 - 66  through a pair of connecting links  82  and a supply port mounting block  84 . Each ink supply port  56 - 66  includes a septum  86  facing a corresponding needle  88  ( FIGS. 15 and 19 ) of printhead module  14 . Needles  88  are protected by a shroud  90  along the top of printhead module  14 . Second lever arm  80  includes a bail  124  for connecting to actuator  122 . Actuator  122  includes a third lever arm  126  operatively connected to latch first part  52  at sixth pivot pins  128 . Actuator lever arm  126  is connectable to latch second part  54  at bail  124  through a hook  130 . Actuator lever arm  126  includes a handle  132  for the user to grasp while operating actuator  122 . 
         [0038]    The operation of this embodiment of latch  50  will now be described with reference to  FIGS. 19-25 . Detail views  FIGS. 22A ,  22 B,  23 A, and  23 B are provided for clarity. Different line types are used in the elevation views of  FIGS. 19-23  to help distinguish between overlapping parts. Direction arrows  131  indicate the motion of actuator lever arm  126  in FIGS.  19  and  21 - 23 . 
         [0039]    Referring to  FIGS. 19-21 , the user grasps handle  132  on actuator  122  to rotate first lever arm  68  clockwise to close latch first part  52 . First lever arm  68  pivots on first pins  92  mounted to carriage  12 . As best seen by comparing  FIGS. 20 and 21 , each pivot arm  72  rotates down (clockwise) with first lever arm  68  until contact surfaces  76  engage corresponding contact surfaces  78  on printhead module  14 . 
         [0040]    Actuator handle  132  pivots on sixth pins  128  to align hook  130  to bail  124  on latch second part  54  as shown in  FIG. 21 . Latch second part  54  may then be closed at the urging of actuator  122  to first put printhead module  14  into the proper, datum position in carriage  12  (compare  FIGS. 20 and 21 ) and then to connect printhead module  14  to ink ports  56 - 66  (compare  FIGS. 22 and 23 ). As best seen by comparing the sequence of  FIGS. 21 ,  22 , and  23 , once actuator  122  is hooked to bail  124 , actuator (third) lever arm  126  pivots on fulcrum pins  128  as handle  132  is rotated counterclockwise. Actuator lever arm  126 , in turn, rotates second lever arm  80  counterclockwise and moves block  84  carrying ink supply ports  56 - 66  toward needles  88 . During this part of the operation, second lever arm  80  pivots on third pin  106  mounted to carriage  12 . Connecting link  82  pivots on fourth pin  112  on block  84  and fifth pin  114  on second lever arm  80 . Thus, connecting link  82  converts the rotating motion of second lever arm  80  into a linear motion of block  84  carrying supply ports  56 - 66 . As shown in  FIG. 23 , when latch part  54  is fully closed each needle  88  pierces the corresponding supply port septum  86  to make the ink connections to printhead module  14  through supply ports  56 - 66 . 
         [0041]    In this embodiment of latch  50 , latch second part  54  includes a lock  134  that blocks the unintended or inadvertent operation of latch second part  54 . As best seen in  FIG. 18 , lock  134  is constructed as a pair of spring tabs  134  positioned on opposite sides of mounting block  84 . A key  136  on actuator  122  unlocks lock  134  as actuator  122  is rotated counterclockwise to begin closing latch second part  54 . As best seen by comparing the elevation views of  FIGS. 21-23  and the section views of  FIGS. 24 and 25 , keys  136  push tabs  134  inboard, off the corresponding stops  137  on carriage  12 , to allow second lever arm  80  to pivot, thus unlocking latch second part  54 . 
         [0042]    Also in this embodiment of latch  50 , first lever arm  68  is “over-rotated” to compress biasing spring  74  and exert added pressure on printhead module  14  as septa  86  are pushed on to and pulled off of needles  88 . This added pressure helps keep printhead module  14  seated and stationary during the time when maximum force is exerted making and breaking the ink supply connections. As best seen by comparing  FIGS. 21 and 22 , as actuator lever arm  126  is rotated counterclockwise to close latch second part  54 , it drives the distal end  138  of first lever arm  68  down just as septa  86  reach needles  88 . This clockwise rotation of first lever arm  68  rotates pivot arm  72  clockwise to drive contact surface  76  into printhead module  14  (at contact surface  78 ) and compress biasing spring  74 . Then, as actuator lever arm  126  continues to rotate to the fully closed position for latch part  54  (where needles  88  have pierced septa  86 ), shown in  FIG. 23 , it pulls the end  138  of first lever arm  68  up to release the added pressure. In the same way, added pressure is exerted as actuator lever  126  is rotated up (clockwise) to open latch second part  54  and withdraw septa  86  from needles  88 . 
         [0043]    As noted at the beginning of this Description, the embodiments shown in the figures and described above illustrate but do not limit the invention. Other embodiments are possible. Therefore, the foregoing description should not be construed to limit the scope of the invention, which is defined in the following claims.