Patent Publication Number: US-6334663-B1

Title: Service station device for ink-jet printer

Description:
CLAIM OF PRIORITY 
     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 arising from an application for Service Station Device For Ink-Jet Printer earlier filed in the Korean Industrial Property Office on Mar. 28, 1996 and there duly assigned Ser. No. 6251/1996. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a service station device for an ink-jet printer which serves to clean and seal a nozzle of the printer&#39;s head. More particularly, it relates to a service station device for an ink-jet printer which can effectively clean and seal a nozzle of the printer head with a rotary motion of a cap and has the more improved capping function by restricting movement of a carriage for carrying the printer head during a sleep mode of the printer. 
     DISCUSSION OF RELATED ART 
     There are many patents that discuss sealing and capping means for the nozzle of an ink jet printer. For example, U.S. Pat. No. 5,471,230 for a Capping Means and Ink Jet Recording Apparatus Using The Same to Saito et al., U.S. Pat. No. 5,448,270 for an Ink-Jet Printhead Cap Having Suspended Lip to Osborne and U.S. Pat. No. 5,426,456 for a Suction and Covering Device For Suctioning Ink From Ink Print Heads of an Ink Jet Print Unit and For Sealing The Ink Jet Print Heads to Kuelzer et al. each discuss a means for capping a nozzle for an ink-jet printer to prevent leakage of ink. However, what is missing is a way for positioning the cap exactly to fit over the nozzle of an ink jet printer to prevent the unwanted leakage of ink when the nozzle is supposed to be capped. Also, what is not discussed is a mechanism for preventing the inadvertent detachment of the cap from the nozzle of the ink-jet printer if the ink jet printer is inadvertently bumped or moved while the printer is not printing. In such a scenario, is desirable to have the cap remain attached to the nozzle so as to prevent the leakage of ink. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a device that substantially obviates one or more of the problems, limitations and disadvantages of the related art. 
     It is an objective to provide a service station device for an ink-jet printer which can clean a nozzle of a printer head and exactly seal the nozzle with its cap to prevent loss of ink and problems of the nozzle. 
     The above and other objects are achieved, according to the invention, by the provision of a service station device for an ink-jet printer, the service station device including: a housing secured in a service area of a printer and having first guide slots and second guide slots formed in both side walls thereof, the guide slots being disposed in a line and said second guide slots each having an upper straight portion and a lower inclined portion; a moving member disposed in said housing to be moved to a position for capping and sealing an ink nozzle by a carriage and forced toward a printing area by a spring secured on a bottom of the housing, and having front and rear guide pins guided along the first and second guide slots, respectively; a wiper member having a wiper for cleaning the nozzle and being pivotally mounted to the housing, the wiper member being in a position for cleaning the nozzle when the rear guide pins are in a lower end of the second guide slots; and a capping and sealing member having a cap for capping and sealing the nozzle, the cap capping and sealing the nozzle when the rear guide pins begin to move to the upper straight portion of the second guide slots from the lower inclined portion thereof. 
     Alternatively, the above and other objects also can be achieved according to the present invention, by the provision of a service station device for an ink-jet printer, the service station device including: a housing secured in a service area of a printer and having first guide slots and second guide slots formed in both side walls thereof, the guide slots being disposed in a line and the second guide slots each having an upper straight and a lower inclined portion; a moving member disposed in the housing to be moved a position for capping and sealing an ink nozzle by a carriage and forced toward a printing area by a spring secured on a bottom of the housing, and having front and rear guide pins guided along the first the said second guide slots, respectively; a wiper member having a wiper for cleaning the nozzle and being pivotally mounted to the housing, the wiper member being pivoted to a position for cleaning the nozzle by the moving member forced toward the printing area by the spring; and a capping and sealing member having a cap for capping and sealing the nozzle, the cap capping and sealing the nozzle when the rear guide pins begin to move to the upper straight portion of the second guide slots from the lower inclined portion thereof. 
     The service station device according to the present invention may further include a locking member provided on a frame of the printer and forced toward the carriage by a resilient member, to hold the nozzle in the capping and sealing position. 
     The wiper member includes a wiper body formed by a pair of plates, and pin members inserted pivotally into holes formed on both side walls of the housing; the wiper is positioned adjacent to a free end of the wiper body. 
     The capping and sealing member includes a biasing member biasing the cap upwardly. The cap includes a shaft inserted into a hole formed in the moving member and a catch for preventing the cap from separating from the hole, and the biasing member is disposed around the shaft. 
     The cap has preferably a height such that the cap is slightly pressed by the nozzle when the nozzle is sealed in the capping and sealing position by the cap. 
     The moving member includes a touch guide uprightly provided on a front portion thereof, and a spring barb positioned below the t ouch guide to extend downwardly, the touch guide being forced to the capping and sealing position by the carriage moving to the capping and sealing position, and the spring barb is connected with the spring for forcing the moving member to a printing position. 
     The housing has a stopper provided at rear end there of for supporting the wiper member when the moving member is moved the capping and sealing position. 
     The locking member includes an elongated snap piece fixed on a frame and having a rounded projection formed at an end thereof, and a resilient member for pulling the elongated snap piece toward a side of the carriage, the rounded projection being engaged with a rounded recess formed at the side of the carriage. A resilient force of the resilient member is smaller than a moving force of the carriage. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory, and are intended to provide further explanation of the invention as claimed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of this invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which like reference symbols indicate the same or similar components, wherein: 
     FIG. 1 schematically depicts a conventional ink-jet printer with printing and service zones; 
     FIG. 2 is a longitudinally-sectional view of a conventional service station device for an ink-jet printer; 
     FIG. 3 is a sectional view for describing the operating mechanism of the conventional service station device; 
     FIG. 4 is an exploded perspective view of a service station device for an ink-jet printer in accordance with the present invention; 
     FIG. 5 is a plan view of the service station device in accordance with the present invention; 
     FIG. 6 is a longitudinally-sectional view of a service station device for an ink-jet printer in accordance with the present invention; 
     FIG. 7 is a sectional view for describing the operating mechanism of the inventive service station device; 
     FIG. 8 is a sectional view as taken along line A-A′ of FIG. 7; and 
     FIG. 9 is a perspective view of a carriage locking member of FIG.  8 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning to FIG. 1, in a conventional ink-jet printer a carriage  2 , on which a head  1  is mounted, the head  1  is slid right and left by a timing pulley  4  and a belt  4 ′ driven by a forwarding/reversing motor  3 . The carriage  2  is moved along a guide shaft  6  fixed on a main body frame  5 , in a straight line. 
     Therefore, the head  1  is moved along a guide shaft  6  by the carriage  2  and performs a printing by injecting ink on paper through a nozzle  7  provided on a bottom surface thereof. This printing operation is carried out in a printing area of the printer while the paper is passing through the printer. Adjacent to the printing area, there is disposed a service area in which the nozzle  7  is cleaned and sealed to prevent loss of ink. The cleaning and the capping of the nozzle  7  are carried out by a service station device. The service station device includes a means for cleaning the nozzle  7  according to a cleaning signal of the controller, and a means for capping and sealing nozzle  7  to prevent loss of ink. 
     FIG. 2 is a conventional service station device  10 . This service statio n device  10  has a housing  11  fixed on a bottom surface of the main body frame  5 . The housing  11  is rectangular shaped, and has a rectangular space  11   a  in its interior, in which a cleaner  20  and a capping assembly  30  are installed. The cleaner  20  includes a wiper body  22  on which a wiper  21  made of rubber is fixedly mounted, and the wiper body  22  is pivoted about a point  23  (FIG.  3 ). The capping assembly  30  includes a moving member  31 , and the guide projections  32  are moved along guide slots  12  formed in both side walls of the housing  11  moved in the space  11   a , and guide projections  32  are formed on both sides of the moving member  31 . A touch guide  33  is uprightly provided on the moving member  31 , opposite to the guide projection  32 , so that moving member  31  is pushed to the s service area by the carriage  2  when the carriage  2  is moved to the service area. In addition, a cap  35  for capping and sealing the nozzle  7  is installed on the moving member  31 , and the cap  35  is biased upwardly by spring force of a spring  34 . 
     Each of the guide slots  12  has a same shape as a sliding face  13  formed inside of the housing  11 , and a straight lower surface  31   a  of the moving member  31  contacts with the sliding face  13 , so that the straight lower surface  31   a  can move along a sliding face  13  when the moving member  31  is moved. The moving member  31  has a straight lower surface  31   a  and an inclined lower surface  31   b , and the straight lower surface  31   a  is substantially shorter than the inclined lower surface  31   b.    
     The sliding face  13  has a lower sliding area  13   a  positioned at a central portion of the housing  11  and an upper sliding area  13   b  positioned at one side of the housing  11 . An inner edge  14  of the upper sliding area  13   b  is rounded, which is a starting point of the upper sliding area  13   b . The straight lower surface  31   a  is positioned on the lower sliding area  13   a  and an upper portion of the inclined lower surface  31   b  is contacted with the inner edge  14  of the upper sliding area  13   b  when the carriage  2  is in the printing area, as shown in FIG.  2 . 
     The moving member  31  positioned in the space  11   a  is biased toward the printing area by a spring  40 , of which both ends are secured to a front-lower portion of the moving member  31  and the bottom of the housing  11 , respectively. The wiper body  22  is supported by the moving member  31  to be maintained horizontally. 
     The carriage  2  is moved from the printing area and to the service area for cleaning and/or capping and sealing the nozzle  7  of the printer head  1  when the printer is turned off or when the nozzle  7  is periodically cleaned. The nozzle  7  is contacted with a wiping surface of the wiper  21  to thereby remove a residuary ink on the nozzle  7  while the nozzle  7  is passed through the wiper  21 , as shown in FIG.  2 . 
     After the nozzle  7  is cleaned by the wiper  21 , the moving member  31  is moved to a position shown in FIG. 3 by the carriage  2  and the wiper body  22  is pivoted about the point  23  downwardly, as the touch guide  33  provided uprightly on the moving member  31  is pushed by the carriage  2 . At this time, the moving member  31  is rising upwardly since the inclined lower surface  31   b  is slid upon the inner edge  14  and the guide projections  32  are guided along the guide slots  12 . 
     When the moving member  31  is stopped, the lower surface  31   a  is positioned on the upper sliding area  13   b , and the nozzle  7  is sealed by the cap  35  biased upwardly by the spring  34 . The cap  35  is not separated from the nozzle  7  until the carriage  2  is returned to the printing area to prevent loss of the ink. When the carriage  2  is returned to the printing area, the moving member  31  is returned to a ready position (as shown in FIG. 2) by the spring force of the spring  40 . 
     In the conventional service station device  10 , the moving member  31  has a relative larger elevation and descent distance h, and the larger the distance h becomes, the more difficult it is to exactly cap and seal the nozzle  7  with the cap  35 . 
     Therefore, it is preferable to design the moving member having a smaller elevation and descent distance h, but this is not easy because the moving member is moved along with the carriage to seal the nozzle. 
     Also, during the sleep mode of the printer, because a binding force of the timing belt acts on the carriage, but this binding force is substantially small, the carriage may be released from the service area when shipping the printer to another place. The moving member may escape from the sealing position as held by the spring due to the moving of the carriage, so that the capping of the nozzle may be released. This may cause the ink on the nozzle to dry, which causes problems of the nozzle. 
     Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
     FIGS. 4 to  9  depict a service station device  100  for an ink-jet printer in accordance with the present invention. 
     In the service station device  100  a housing  110  is fixedly mounted in a service area of a frame  5  of the printer main body (see FIG.  6 ). A cleaner  200  has a wiper  210 , which is made from rubber, for cleaning a nozzle  7  of a printer head  1  which is mounted to a carriage  2  and moved between the service area and a printing area by the carriage  2 , and is installed pivotally to both side walls of the housing  110 . A capping assembly  300  has a cap  350  for sealing the nozzle  7  of the printer head  1  and is installed in first guide slots  140  and second guide slots  140 ′ formed in both side walls of the housing  100  such that the capping assembly  300  is moved along the guide slots  140  and  140 ′. 
     Preferably, a locking member  400  may be provided in the service station device  100  for locking the carriage  2  to prevent the sealing of the nozzle  7  from releasing when the nozzle  7  is capped and sealed by the cap  350 . The locking member  400  is mounted to the frame  5  of the printer main body. 
     The housing  110  is formed by injection-molding materials such as a plastic resin in rectangular form, and has a space  111  formed therein for receiving the cleaner  200  and the capping assembly  300 . The first guide slots  140  are disposed adjacent one side of the housing  110  and a portion of the second guide slots  140 ′ are disposed in a line with the first guide slots  140  adjacent the other side of the housing  110 , as shown in FIG.  4 . The holes  120  are disposed adjacent to an inclined portion  140 ′ a  of the second guide slots  140 ′, respectively. 
     The cleaner  200  has a wiper body  220  formed by a pair of plates  221  and disposed within the space  111 . The wiper  210  is positioned uprightly between the plates  221 , a pair of pin members  230  are disposed at a pivot end  222  of the wiper body  220 , respectively, and the pin members  230  extend laterally from the wiper body  220  and are pivotally inserted into the holes  120 . The wiper body  220  is disposed at rear end of the housing  110  and has a slant guide surface  223  below the pivot end  222 , as shown in FIG.  4 . When the cleaner  200  is positioned horizontally, a lower end of the slant guide surfaces  223  is disposed above a lower end of the inclined portion  140 ′ a  of the second guide slots  140 ′, as shown in FIG.  6 . 
     The capping assembly  300  has a rectangular moving member  310  having two pairs of guide pins  380  and  380 ′ extending laterally at both sides of front and rear portions thereof, respectively. The pairs of guide pins  380  and  380 ′ are inserted into the first guide slots  140  and the second guide slots  140 ′ of the housing  110 , respectively. The moving member  310  also has a hole  311  into which the cap  350  is inserted, and a touch guide  330  is uprightly provided on a front portion of the moving member  310 , and a spring barb  360  is positioned below the touch guide  330  to extend downwardly. 
     The cap  350  is made from rubber and has a shaft  352  for connecting the cap  350  to the moving member  310 , and a catch  351  which is forced into the hole  311  on the moving member  310  and prevents the cap  350  from separating from the hole  311 . When the cap  350  is installed to the moving member  310 , the cap  350  is biased upwardly by a biasing member  353  which is disposed around the shaft  352 . The cap  350  has a height such that the cap  350  is slightly pressed by the nozzle  7  when the nozzle  7  is sealed by the cap  350 . Therefore, the cap  350  can surely seal the nozzle  7  when the nozzle  7  is in a capping position. 
     The touch guide  330  is pushed toward outside of the housing  110  by the carriage  1  moved from the printing area to the service area. The spring barb  360  is secured with one end of a spring  370  for pulling the moving member  310  to the printing area, of which other end is secured to a spring fixing piece  112  which is provided on a bottom of the housing  100 . Therefore, the moving member  310  is forced to the printing area by the spring  370  when the carriage  2  is in the printing area, as shown in FIG.  6 . 
     The locking member  400  serves to prevent the movement of the carriage  2  when the nozzle  7  is in the capping position As shown in FIG. 8, the locking member  400  includes an elongated snap piece  420  having a rounded projection  421  formed at an end thereof and movable laterally, and a resilient member  430  for pulling the elongated snap piece  420  toward the side of the carriage  2 . A resilient force of the resilient member  430  is smaller than the moving force of the carriage  2 . 
     The elongated snap piece  420  is fixed to the frame  5  of the service area to which the carriage  2  is moved, and both ends of the resilient member  430  are respectively secured to a middle portion of the elongated snap piece  420  and the frame  5 . 
     The locking projection  421  is engaged with a rounded recess  410  formed at the side of the carriage  2  by the resilient member  430  when the carriage  2  is in the service area due to turning off the printer, or for cleaning the nozzle  7  periodically, as shown in FIG.  8 . The engagement between the rounded projection  421  and the rounded recess  410  by the resilient member  430  is released when the carriage  2  is moved to the printing area from the service area since the resilient force of the resilient member  430  is smaller than the moving force of the carriage  2 . 
     The service station device according to the present invention operates as follows: 
     The carriage  2 , on which the head  1  is mounted, is moved toward the service area from the printing area, when the printer is turned off or when it is necessary to clean the nozzle  7  periodically. 
     FIG. 5 shows the initial state of a service station device according to the present invention, and FIG. 6 shows that the nozzle  7  is cleaned by the wiper  210  of cleaner  200  while the carriage  2  is moved to the service area from the printing area. As shown in FIGS. 5 and 6, a lower surface  220   a  of the wiper body  220  is supported by the rear guide pins  380 ′ of the moving member  310  which is forced to the printing area by the spring force of the spring  370 , so that the wiper body  220  is disposed horizontally and the wiper  210  is disposed uprightly to contact with and to clean the nozzle  7 . 
     Because the rear guide pins  380 ′ of the moving member  310  are positioned at the lower end of the inclined portion  140 ′ a  of the second guide slots  140 ′ and the front guide pins  380  are positioned at a rear end of the first guide slots  140 , the moving member  310  is obliquely disposed by a position difference between the guide pins  380 ′ and  380 , as shown in FIG.  6 . Accordingly, the touch guide  330  uprightly provided on the front portion of the moving member  310  also is obliquely disposed. At this time, the upper end of the touch guide  330  is positioned on a moving path of the carriage  2 . 
     The touch guide  330  is forced to the service area by the carriage  2  and the moving member  310  is moved to a position for sealing the nozzle  7  against the spring force of the spring  370 , as shown in FIG. 7, as the carriage  2  is continuously moved to the service area after the nozzle  7  is cleaned by the wiper  210  as shown in FIG.  6 . 
     The guide pins  380  and  380 ′ provided at both sides of front and rear portions of the moving member  310  are moved along the first guide slots  140  and the second guide slots  140 ′ and the nozzle  7  is sealed by the cap  350  at a point where there is finished the inclined portion  140 ′ a  of the second guide slots  140 ′, while the moving member  310  is moved to the capping position of the nozzle  7 . Accordingly, the moving member  310  is moved to the capping position under condition that the nozzle  7  is sealed by the cap  350  while the rear guide pins  380 ′ are moved along a straight portion  140 ′ b  of the second guide slots  140 ′. 
     On the other hand, when the moving member begins to move to the capping position by the carriage  2 , the wiper body  220  begins to pivot downwardly about the pins  230  by a self-weight thereof, since the rear guide pins  380 ′, by which the lower surface  220   a  of the wiper body  220  is supported, is moved to the capping position along the inclined portion  140 ′ a . The wiper body  220  is pivoted continuously and downwardly about the pins  230  until the lower surface  220   a  is supported by a stopper  130  provided at a rear side of the housing  110 . Accordingly, the wiper  210  is positioned below the cleaning position when the nozzle  7  is sealed by the cap  350 . 
     The locking member  400  is operated by contacting with a leading end of the carriage  2  when the carriage  2  is moved to the capping position. As the rounded projection  421  of the elongated snap piece  420  is contacted with the leading end of the carriage  2 , the elongated snap piece  420  is slightly pivoted outwardly against the resilient member  430 , and then the rounded projection  421  is received in the rounded recess  410  formed at the side of the carriage  2  by the resilient member  430  when the nozzle  7  arrives in the capping position. Therefore, the carriage  2 , i.e., the nozzle  7  can be maintained in the capping position by the locking member  400  during the turnoff of the printer, or the capping and sealing of the nozzle  7 , as shown in FIGS. 7 and 8. When the nozzle  7  is sealed with the cap  350  by turning off the printer, or by capping and sealing it, as shown in FIGS. 7 and 8, if the carriage  2  begins to move to the printing position, the rounded projection  421  is separated from the rounded recess  410  to release the locking of the carriage  2  by the locking member since the resilient force of the resilient member  430  is smaller than the moving force of the carriage  2 , as above described. 
     The moving member  310  is moved to the position shown in FIG. 6 by the spring force of the spring  370 . The capping of the nozzle  7  by the cap  350  is released at the point where the straight portion  140 ′ b  of the second guide slots  140 ′ is finished and the inclined portion  140 ′ a  is begun. 
     The wiper body  220  is pivoted upwardly by the rear guide pins  380 ′ and is positioned horizontally to clean the nozzle  7  when the nozzle  7  passes through the cleaning position, as the rear guide pins  380 ′ are moved downwardly along the inclined portion  140 ′ a  of the second guide slots  140 ′ and positioned at the lower end of the inclined portion  140 ′ a.    
     The moving member has a relative small elevation and descent distance since the lower surface of the wiper body is supported by the stopper provided at the rear side of the housing. Accordingly, capping and sealing the nozzle by the cap can be easy. 
     Also, during the sleep mode of the printer, although the carriage may be released from the service area when shipping the printer to another place, the moving member can be prevented from escaping from the sealing position, since the carriage is locked in the capping position by means of the locking member. Also, although the moving member can move from the capping position, the nozzle is prevented from loss of sealing since the capping of the nozzle can be maintained for a certain distance as the moving member moves in the first guide slots. Accordingly, the drying of the nozzle can be prevented, avoiding problems of the nozzle. 
     As described above, in the service station device of the present invention, as the nozzle is not only cleaned by the wiper but also capped and sealed by the cap, in correct positions, the nozzle can carry out its function without error. 
     It will be apparent to those skilled in the art that various modifications and variations can be made in the service station device for an ink jet printer of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.