Patent Publication Number: US-9889999-B2

Title: Sheet supplying device, sheet storing device, sheet using apparatus, and liquid discharging apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is based on and claims priority pursuant to 35 U.S.C. § 119(a) to Japanese Patent Application No. 2015-224202, filed on Nov. 16, 2015, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein. 
     BACKGROUND 
     Technical Field 
     The present disclosure relates to a sheet supplying device, a sheet storing device, a sheet using apparatus, and a liquid discharging apparatus. 
     Description of the Related Art 
     A sheet supplying device is known which separates and supplies stacked sheets one by one. In particular, a friction-type sheet supplying device is known which uses a separation pad (friction pad) for separating sheets. However, this type of sheet supplying device has low robustness with respect to variation in sheet thickness and is likely to cause multiple feeding or non-feeding. 
     SUMMARY 
     In accordance with some embodiments of the present invention, a sheet supplying device is provided. The sheet supplying device includes a separator to separate sheets one by one. The separator includes a separation pad, a spring, and a separation pressure adjuster. The separation pad contacts each of the sheets. The spring applies a separation pressure to the separation pad. The separation pressure adjuster adjusts the separation pressure to one of separation pressure values variable in multiple steps. 
     In accordance with some embodiments of the present invention, a sheet storing device is provided. The sheet storing device includes a container to contain sheets and a separator to separate the sheets contained in the container one by one. The separator includes a separation pad, a spring, and a separation pressure adjuster. The separation pad contacts each of the sheets. The spring applies a separation pressure to the separation pad. The separation pressure adjuster adjusts the separation pressure to one of separation pressure values variable in multiple steps. 
     In accordance with some embodiments of the present invention, a sheet using apparatus is provided. The sheet using apparatus includes the above sheet storing device and a liquid discharger to discharge a liquid on the sheet to form an image. 
     In accordance with some embodiments of the present invention, a liquid discharging apparatus is provided. The liquid discharging apparatus includes the above sheet storing device and a liquid discharger to discharge a liquid on the sheet to form an image. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
         FIG. 1  is a perspective outline view of a sheet using apparatus according to an embodiment of the present invention; 
         FIG. 2  is a perspective view of a mechanical section of the sheet using apparatus illustrated in  FIG. 1 ; 
         FIG. 3  is a plan view of a major part of the mechanical section illustrated in  FIG. 2 ; 
         FIG. 4  is a side view of a carriage included in the sheet using apparatus illustrated in  FIG. 1 ; 
         FIGS. 5 and 6  are cross-sectional and perspective views, respectively, of a sheet supplying device according a first embodiment of the present invention, attached to a supply cassette; 
         FIGS. 7 and 8  are perspective and elevation views of a spring holder included in the sheet supplying device illustrated in  FIGS. 5 and 6 ; 
         FIG. 9  is a perspective view of a major part of a sheet supplying device according to a second embodiment of the present invention; 
         FIG. 10  is a perspective view of a spring holder included in a sheet supplying apparatus according to a third embodiment of the present invention; 
         FIG. 11  is a plan view of the spring holder illustrated in  FIG. 10  mounted on a holder receiver; 
         FIGS. 12A and 12B  are side views of a major part of a sheet supplying device according to a fourth embodiment of the present invention; 
         FIGS. 13 and 14  are side and elevation views, respectively, of a major part of a sheet supplying device according to a fifth embodiment of the present invention; 
         FIGS. 15 and 16  are side and elevation views, respectively, of a major part of a sheet supplying device according to a sixth embodiment of the present invention; 
         FIG. 17  is a side view of a major part of a sheet storing device according to a seventh embodiment of the present invention; 
         FIG. 18  is a side view of a major part of a sheet storing device according to an eighth embodiment of the present invention; 
         FIG. 19  is a perspective view of a container included in the sheet storing device illustrated in  FIG. 18 ; and 
         FIG. 20  is a magnified perspective view of a major part of the container illustrated in  FIG. 19 . 
     
    
    
     The accompanying drawings are intended to depict example embodiments of the present invention and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. 
     DETAILED DESCRIPTION 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes” and/or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Embodiments of the present invention are described in detail below with reference to accompanying drawings. In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner and achieve a similar result. 
     For the sake of simplicity, the same reference number will be given to identical constituent elements such as parts and materials having the same functions and redundant descriptions thereof omitted unless otherwise stated. 
     In accordance with some embodiments of the present invention, a sheet supplying device is provided which easily properly adjusts the separation pressure. 
     A sheet using apparatus according to an embodiment of the present invention is described below with reference to  FIGS. 1 to 4 .  FIG. 1  is a perspective outline view of a sheet using apparatus according to an embodiment of the present invention.  FIG. 2  is a perspective view of a mechanical section of the sheet using apparatus illustrated in  FIG. 1 .  FIG. 3  is a plan view of a major part of the mechanical section illustrated in  FIG. 2 .  FIG. 4  is a side view of a carriage included in the sheet using apparatus illustrated in  FIG. 1 . 
     The sheet using apparatus illustrated in  FIG. 1  is configured to discharge a liquid onto a sheet to form an image thereon. The sheet using apparatus includes an apparatus body  101 , a supply cassette  102  serving as a sheet storing device, and an ejection tray  103  for stacking ejected sheets thereon. The supply cassette  102  is detachably attached to a front surface side of the apparatus body  101 . The ejection tray  103  is disposed above the supply cassette  102 . 
     On a right side of the front surface of the apparatus body  101 , a cover  104  is disposed. The cover  104  is openable and closable. When the cover  104  is opened, a liquid cartridge  62  can be attached to or detached from a cartridge holder  61  disposed in the apparatus body  101 . 
     In the mechanical section, as illustrated in  FIGS. 2 and 3 , a guide member  3 , formed of a platy member, is stretched between a pair of side plates  1 A and  1 B, and a carriage  4  is supported by the guide member  3  so as to be movable in the main scanning direction. A main scanning motor  5  moves the carriage  4  in the main scanning direction via a timing belt  8  that is wound around a driving pulley  6  and a driven pulley  7 . 
     The guide member  3  is a platy member that guides movement of the carriage  4 . The guide member  3  has a guide surface  3   a  serving as a support surface for guiding the carriage  4 , and other guide surfaces  3   b  and  3   c.    
     The carriage  4  has a rodless guide mechanism including a height adjuster  4   a , a contact part  4   b , and another contact part  4   c . The height adjuster  4   a  is movably supported by the guide surface  3   a  of the guide member  3 . The contact part  4   b  movably contacts the guide surface  3   b  of the guide member  3 . The contact part  4   c  movably contacts the guide surface  3   c  of the guide member  3 . 
     The carriage  4  includes heads  11   a  and  11   b  (hereinafter may be collectively “heads  11 ”) for discharging liquids. Each of the heads  11   a  and  11   b  has two nozzle arrays. The four nozzle arrays, in total, are assigned to discharge liquids of yellow, cyan, magenta, and black, respectively. 
     The heads  11   a  and  11   b  integrally support respective head tanks  12   a  and  12   b  (hereinafter may be collectively “head tanks  12 ”) for supplying liquids. 
     In the apparatus body  100 , the liquid cartridge  62  is detachably mountable on the cartridge holder  61 . A pump unit  63  supplies a liquid contained in the liquid cartridge  62  to the head tanks  12  via a supply tube  64  (illustrated in  FIG. 2 ). 
     An encoder scale  15  is disposed along the main scanning direction of the carriage  4 . An encoder sensor  16  for reading the scale of the encoder scale  15  is mounted on the carriage  4 . The encoder sensor  16  is formed of a transmission photosensor. The encoder scale  15  and the encoder sensor  16  form a linear encoder serving as a position detector. 
     Below the carriage  4 , a conveyance belt  21  for conveying a sheet  10  in the sub-scanning direction is disposed. The conveyance belt  21  is an endless belt stretched between a conveyance roller  22  and a tension roller  23 . A sub-scanning motor  31  rotary-drives the conveyance roller  22  via a timing belt  32  and a timing pulley  33 , to cause the conveyance belt  21  to circumferentially move in the sub-scanning direction. 
     As illustrated in  FIG. 4 , sheet guide members  51  and  52  are disposed in the vicinity of entrance and exit parts, respectively, of the conveyance belt  21 . 
     On one lateral side of the conveyance belt  21  in the main scanning direction of the carriage  4 , a maintenance unit  41  for maintaining the heads  11  is disposed. 
     The maintenance unit  41  includes a suction cap  42   a  and a moisture-retention cap  42   b  for capping the nozzle surfaces of the heads  11 , a wiper  43  for wiping the nozzle surfaces, and a dummy discharge receptacle  44  for receiving dummy discharge liquid during maintenance. The suction cap  42   a  is connected to a suction pump serving as a suction device. 
     The sheet  10  fed from the supply cassette  102  is intermittently conveyed by the conveyance belt  21 , while the carriage  4  is moved in the main scanning direction and the heads  11  are driven according to an image signal. This operation records one line of an image on the sheet  10  with the liquid discharged from the heads  11 . After conveying the sheet  10  for a predetermined amount, this operation is repeated to record next line of the image on the sheet  10 . Such a sheet-conveying and image-recording operation is repeated until formation of the image is completed. The sheet  10  having the image thereon is ejected from the apparatus body  100 . 
     A sheet supplying device according to a first embodiment of the present invention, usable for the above-described sheet using apparatus, is described below with reference to  FIGS. 5 to 8 .  FIGS. 5 and 6  are cross-sectional and perspective views, respectively, of a sheet supplying device  301  attached to the supply cassette  102 .  FIGS. 7 and 8  are perspective and elevation views of a spring holder  318  included in the sheet supplying device  300 . 
     The supply cassette  102  includes a cassette body  201  for storing multiple sheets  10  and a bottom plate  202  for stacking the sheets  10  thereon. 
     The sheet supplying device  301  includes a supply roller  312  mounted on a shaft  311 . On both axial ends of the supply roller  312 , supply roller collars  313  are respectively disposed. 
     A separator  303  is disposed facing the supply roller  312 . The separator  303  includes a friction pad  314  serving as a separation pad, and a friction pad holder  315  for holding the friction pad  314 . The friction pad holder  315  has a shaft part  315   a  on a downstream side relative to the sheet supplying direction. The shaft part  315   a  is supported by a supply guide member  310  to make the friction pad holder  315  swingable. 
     On the opposite side of the friction pad  314  relative to the friction pad holder  315 , a spring  317  is disposed. The spring  317  applies a separation pressure to the friction pad  314 . The spring  317  is held by a spring holder  318 . The spring holder  318  combines the function of adjusting the separation pressure, to be applied to the friction pad  314 , to separation pressure values preset in multiple steps. 
     The spring holder  318  is movably held by a holder receiver  304 . The spring holder  318  is in contact with one end part a friction pad pressing lever  319 . 
     The friction pad pressing lever  319  has a shaft part  319   a . The shaft part  319   a  is supported by a support  305  (illustrated in  FIG. 6 ) to make the friction pad pressing lever  319  swingable. When the supply cassette  102  is mounted on the apparatus body  101 , a front plate  204 , disposed on a front side of the cassette body  201  in the mounting direction, presses the friction pad pressing lever  319 . The friction pad pressing lever  319  thereby rotates in a direction indicated by arrow in  FIG. 5  to push up the spring holder  318 . 
     The friction pad pressing lever  319  is configured to release the separation pressure. When the supply cassette  102  is unmounted from the apparatus body  101 , the one end of the friction pad pressing lever  319  in contact with the spring holder  318  is separated therefrom and the spring  317  restores to its original state. Thus, the separation pressure is released. 
     Referring to  FIGS. 7 and 8 , the spring holder  318  has spring receiving parts  318   a   1  and  318   a   2  and a mounting part  318   b  to be movably fitted into the holder receiver  304 . 
     When mounted on the holder receiver  304 , the spring holder  318  may be in either a regular posture as illustrated in  FIGS. 7 and 8  or an upside-down posture. 
     When the spring holder  318  in the regular posture is mounted on the holder receiver  304 , the distance between the friction pad pressing lever  319  and the seat of the spring  317  (i.e., the bottom surface of the spring receiving part  318   a   1 ) becomes A. When the spring holder  318  in the upside-down posture is mounted on the holder receiver  304 , the distance between the friction pad pressing lever  319  and the seat of the spring  317  (i.e., the bottom surface of the spring receiving part  318   a   2 ) becomes B. 
     Owing to the above-described configuration, when the supply cassette  102  is mounted on the apparatus body  101 , the cassette body  201  of the supply cassette  102  presses the friction pad pressing lever  319 . The friction pad pressing lever  319  thereby rotates about the shaft part  319   a  in a direction indicated by arrow in  FIG. 5 , thus becoming a state illustrated in  FIG. 5 . 
     As the friction pad pressing lever  319  rotates, the spring holder  318  and the spring  317  are pushed up, and the friction pad holder  315  and the friction pad  314  are eventually pushed up toward the supply roller  312 . 
     At this time, the separation pressure from the friction pad  314  is determined depending on the working length (i.e., compression amount) of the spring  317 . 
     In the initial stage (factory default setting), the spring holder  318  in the regular posture is mounted on the holder receiver  304 . At this time, as described above, the distance between the friction pad pressing lever  319  and the seat of the spring  317  becomes A. 
     When the spring holder  318  is turned upside down as indicated by arrow illustrated in  FIG. 7  and mounted on the holder receiver  304  in the upside-down posture, the distance between the friction pad pressing lever  319  and the seat of the spring  317  is changed to B. 
     As a result, since the contact position of the friction pad  314  with the supply roller  312  is fixed, the working length (i.e., compression amount) of the spring  317  is changed. Thus, the separation pressure is changed in multiple steps (two steps in this case). 
     According to the present embodiment, the separation pressure from the friction pad is adjustable to separation pressure values preset in multiple steps. This configuration achieves much easier and more appropriate adjustment of the separation pressure compared to a case in which the separation pressure is adjustable continuously. 
     The method of changing the mounting posture of the spring holder is not limited to turning the spring holder upside down in the vertical direction. For example, the mounting posture can be varied by rotating the spring holder by 90 degrees. 
     A sheet supplying device according to a second embodiment of the present invention is descried below with reference to  FIG. 9 .  FIG. 9  is a perspective view of a major part of the sheet supplying device according to the second embodiment of the present invention. 
     In the second embodiment, the friction pad pressing lever  319  used in the first embodiment is omitted. As the mounting posture of the spring holder  318  on the holder receiver  304  is changed, the working length (i.e., compression amount) of the spring  317  is changed. Thus, the separation pressure is adjustable in multiple steps. 
     In the present embodiment, the spring holder  318  needs not to be movable so long as the working length (i.e., compression amount) of the spring  317  is variable in accordance with a change in mounting posture on the holder receiver  304 . Therefore, the spring holder  318  in the second embodiment, illustrated in  FIG. 9 , has a different shape from that in the first embodiment. Of course, the spring holder  318  in the second embodiment may have the same shape as that in the first embodiment. 
     A sheet supplying device according to a third embodiment of the present invention is descried below with reference to  FIGS. 10 and 11 .  FIG. 10  is a perspective view of the spring holder  318  included in the sheet supplying device according to the third embodiment.  FIG. 11  is a plan view of the spring holder  318  illustrated in  FIG. 10  mounted on the holder receiver  304 . 
     The spring holder  318  has an improper assembly preventing part  318   c  serving as a posture regulator. A gap G is formed between the improper assembly preventing part  318   c  and the mounting part  318   b . More specifically, the gap G is formed between an outer peripheral wall surface of the mounting part  318   b  and an inner wall surface (i.e., the surface facing the mounting part  318   b ) of the improper assembly preventing part  318   c . The improper assembly preventing part  318   c  has a cutout  318   d . The improper assembly preventing part  318   c  is easily removable by being broken. 
     On the other hand, the holder receiver  304  has guide parts  304   a  and  304   b  for guiding the mounting part  318   b  of the spring holder  318 . The guide part  304   a  has a thickness t 1  less then than the gap G formed by the improper assembly preventing part  318   c . The guide part  304   b  has a thickness t 2  greater than the gap G formed by the improper assembly preventing part  318   c.    
     Thus, in the initial stage, the mounting part  318   b  of the spring holder  318  cannot be mounted on the holder receiver  304  unless the guide part  304   a  of the holder receiver  304  can be fitted into the gap G formed by the improper assembly preventing part  318   c.    
     The initial mounting posture of the spring holder  318  is thus automatically determined and prevented from being mounted on the holder receiver  304  in the upside-down posture. When the improper assembly preventing part  318   c  is removed, the spring holder  318  in the upside-down posture can be mounted on the holder receiver  304 . 
     A sheet supplying device according to a fourth embodiment of the present invention is descried below with reference to  FIGS. 12A and 12B .  FIGS. 12A and 12B  are side views of a major part of the sheet supplying device according to the fourth embodiment of the present invention. 
     In the present embodiment, a spring holder  328  includes a spring receiving part  328   a , a shaft part  328   b , and a lever part  328   c . The shaft part  328   b  is rotatably held by a holder receiver  329 . The lever part  328   c  is to be pressed by the cassette body  201  of the supply cassette  102 . 
     The holder receiver  329  has holding parts  329   a  and  329   b  each disposed at different heights, for holding the shaft part  328   b  of the spring holder  328 . The holder receiver  329  serves as a separation pressure adjuster. 
     The height of the spring holder  328  is varied depending on which one of the holding parts  329   a  and  329   b  is holding the shaft part  328   b  of the spring holder  328 . As the height of the spring holder  328  is varied, the working length (i.e., compression amount) of the spring  317  is varied to vary (adjust) the separation pressure in multiple steps. 
     A sheet supplying device according to a fifth embodiment of the present invention is descried below with reference to  FIGS. 13 and 14 .  FIGS. 13 and 14  are side and elevation views, respectively, of a major part of the sheet supplying device according to the fifth embodiment of the present invention. 
     In the present embodiment, a spring holder  328  includes a spring receiving part  328   a , a shaft part  328   b , and a lever part  328   c . The shaft part  328   b  is rotatably held by a holder receiver. The lever part  328   c  is to be pressed by the cassette body  201  of the supply cassette  102 . 
     The lever part  328   c  of the spring holder  328  is equipped with an adjuster  340 . The adjuster  340  varies the contact distance between the lever part  328   c  and the supply cassette  102  to adjust the separation pressure. 
     The adjuster  340  has a circular disc shape. The adjuster  340  has multiple projections  340   a ,  340   b , and  340   c  each different in height, to be brought into contact with the supply cassette  102 . A rotary knob  341  is attached to the adjuster  340  with a plate spring  342 . 
     As the adjuster  340  rotates, the contact distance between the lever part  328   c  and the supply cassette  102  is varied, the amount of tilt of the spring holder  328  is thereby varied, and the working length (i.e., compression amount) of the spring  317  is thereby varied to vary (adjust) the separation pressure in multiple steps. 
     A sheet supplying device according to a sixth embodiment of the present invention is descried below with reference to  FIGS. 15 and 16 .  FIGS. 15 and 16  are side and elevation views, respectively, of a major part of the sheet supplying device according to the sixth embodiment of the present invention. 
     Similar to the fourth embodiment, a spring holder  358  includes a spring receiving part  358   a , a shaft part  358   b , and a work knob  358   c . The shaft part  358   b  is rotatably held by a holder receiver  359 . 
     The holder receiver  359  has holding parts  359   a  and  359   b  each disposed at different heights, for holding the shaft part  358   b  of the spring holder  358 . In addition, the holder receiver  359  has a fall preventing part  359   c  having elasticity, for preventing the shaft part  358   b  from falling off when held by the holding part  359   a  or  359   b.    
     The height of the spring holder  358  is varied depending on which one of the holding parts  359   a  and  359   b  is holding the shaft part  358   b  of the spring holder  358 . As the height of the spring holder  358  is varied, the working length (i.e., compression amount) of the spring  317  is varied to vary (adjust) the separation pressure in multiple steps. 
     A sheet storing device according to a seventh embodiment of the present invention is descried below with reference to  FIG. 17 .  FIG. 17  is a side view of a major part of the sheet storing device according to the seventh embodiment of the present invention. 
     A sheet storing device  500  includes a container  501  for containing sheets  10  and a separator  503  for separating and supplying the sheets  10  contained in the container  501  one by one. 
     The container  501  includes a container body  601  for storing multiple sheets  10 , a bottom plate  602  for stacking the sheets  10  thereon, and a guide member  610  for guiding the sheets  10  to be fed. 
     Similar to the second embodiment, the separator  503  includes a friction pad  614  serving as a separation pad, and a friction pad holder  615  for holding the friction pad  614 . The friction pad  614  faces the supply roller  312  when the sheet storing device  500  is mounted on the above-described sheet using device. 
     The friction pad holder  615  has a shaft part  615   a  on a downstream side relative to the sheet supplying direction. The shaft part  615   a  is supported by the guide member  610  of the container body  601  to make the friction pad holder  615  swingable. 
     On the opposite side of the friction pad  614  relative to the friction pad holder  615 , a spring  617  is disposed. The spring  617  applies a separation pressure to the friction pad  614 . The spring  617  is held by a spring holder  618 . The spring holder  618  combines the function of adjusting the separation pressure, to be applied to the friction pad  614 , to separation pressure values present in multiple steps. 
     The spring holder  618  is held by a holder receiving part  604  of the guide member  610 . When held by the holder receiving part  604 , the spring holder  618  may be in either a regular posture or an upside-down posture, similar to the first and third embodiments. 
     As the posture of the spring holder  618  held on the holder receiving part  604  is changed, the working length (i.e., compression amount) of the spring  617  is changed. Thus, the separation pressure is adjustable in multiple steps. 
     Similar to the third embodiment, the spring holder  618  and the holder receiving part  604  may include a posture regulator. 
     A sheet storing device according to an eighth embodiment of the present invention is descried below with reference to  FIGS. 18 to 20 .  FIG. 18  is a side view of a major part of the sheet storing device according to the eighth embodiment.  FIG. 19  is a perspective view of a container included in the sheet storing device illustrated in  FIG. 18 .  FIG. 20  is a magnified perspective view of a major part of the container illustrated in  FIG. 19 . 
     A sheet storing device  800  includes a container  801  for containing sheets  10  and a separator  803  for separating and supplying the sheets  10  contained in the container  801  one by one. 
     Similar to the supply cassette  102  of the first embodiment, the container  801  includes a cassette body  901  for storing multiple sheets  10  and a bottom plate  902  for stacking the sheets  10  thereon. 
     Similar to the sheet supplying device  301  according to the first embodiment, the separator  803  includes a friction pad  914  serving as a separation pad, and a friction pad holder  915  for holding the friction pad  914 . The friction pad  914  faces the supply roller  312  when the sheet storing device  800  is mounted on the above-described sheet using device. 
     The friction pad holder  915  has a shaft part  915   a  on a downstream side relative to the sheet supplying direction. The shaft part  915   a  is supported by a guide member  910  to make the friction pad holder  915  swingable. 
     On the opposite side of the friction pad  914  relative to the friction pad holder  915 , a spring  917  is disposed. The spring  917  applies a separation pressure to the friction pad  914 . 
     The spring  917  is held by a spring holder  918 . The spring holder  918  is movably held by a holder receiver  904 . 
     The spring holder  918  is in contact with one end part a friction pad pressing lever  919 . The friction pad pressing lever  919  has a shaft part  919   a . The shaft part  919   a  is supported by a support  905  to make the friction pad pressing lever  919  swingable. 
     The cassette body  901  of the container  801  is equipped with an adjuster  940 , similar to the adjuster  340  of the fifth embodiment, disposed on a front side of the cassette body  901  relative to the mounting direction thereof. The adjuster  940  varies the amount of rotation of the friction pad pressing lever  919 . 
     The adjuster  940  has a circular disc shape. The adjuster  940  has multiple projections  940   a ,  940   b , and  940   c  each different in height, to be brought into contact with the friction pad pressing lever  919 . 
     As the adjuster  940  rotates, one of the projections  940   a ,  940   b , and  940   c  to be brought into contact with the friction pad pressing lever  919  is changed, and the amount of rotation of the friction pad pressing lever  919  when the container  801  mounted is thereby varied. 
     As the amount of rotation of the friction pad pressing lever  919  is varied, the amount of movement of the spring holder  918  is varied, and the working length (i.e., compression amount) of the spring  917  is thereby varied to vary (adjust) the separation pressure in multiple steps. 
     In the above-described embodiments, the sheet using apparatus serves as a liquid discharging apparatus, the sheet supplying device supplies sheets to the liquid discharging apparatus, and the sheet storing device stores sheets to be supplied to the liquid discharging apparatus. The sheet using apparatus may be configured to form (record, print) not only an image (including tests and graphics) but also a circuit pattern on a sheet material. 
     Numerous additional modifications and variations are possible in light of the above teachings. It is therefore to be understood that, within the scope of the above teachings, the present disclosure may be practiced otherwise than as specifically described herein. With some embodiments having thus been described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the scope of the present disclosure and appended claims, and all such modifications are intended to be included within the scope of the present disclosure and appended claims.