Abstract:
An eraser dispenser is provided which can store in a dispenser body an eraser longer than the overall length of the dispenser body. The eraser dispenser enables the eraser to be used without replacement with a new one for a long period of time. The eraser dispenser includes: a dispenser body which is enclosed by an outer circumferential wall having a distal opening and has a storing chamber capable of storing therein an eraser that is longer than the overall length of the dispenser body; and a cover which covers the dispenser body. The eraser dispenser further includes; an external operation member which partially projects from the outer circumferential wall and is operated from the outside of the dispenser body; a driving roller which is operated by the external operating member; a receiving member which is disposed opposite to the driving roller with the eraser held therebetween; and a stopper which prevents a rotary button as the external operation member from undergoing reverse turn.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an eraser dispenser capable of appropriately advancing an eraser that is longer than the overall length of its dispenser body by use of an externally operating member. 
   2. Description of the Prior Art 
   As described in, for example, Japanese Utility Model Publication No. 5-1426, an eraser dispenser of this type has been configured such that a stick-shaped eraser is received in a tubular container and is advanced by knock operation for use. Since the stick-shaped eraser that is shorter than the overall length of the container is stored in the container, the eraser has to be reduced in length in order to make the container compact in size. Consequently, the eraser stored in the container is consumed for a short period of time. Thus, there is a frequent need to replace a worn eraser with a new one, causing cumbersome handling. Another patent document is Japanese Utility Model Publication No. 7-56233. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide an eraser dispenser that can accommodates in its dispenser body an eraser, which is worn away for a short period of time in terms of its nature and circumstances, and which is longer than the overall length of the dispenser body so as to make longer intervals for replacement of the eraser. 
   It is another object of the present invention to provide an eraser dispenser whose dispenser body can be shaped freely in terms of configuration, thereby providing uniqueness for its design. 
   It is yet another object of the present invention to provide an eraser dispenser having excellent operability such that the eraser that has been extended is prevented from retracting into the dispenser body due to a pressing force exerted on the paper or the like through the eraser during its use. 
   It is still another object of the present invention to provide an eraser dispenser whose eraser can be shaped more freely in section as compared with the stick-shaped eraser used in a conventional chuck-holding type dispenser, so that an eraser deformed in section can be used by allowing the section of a holding roller, chuck or the like to conform therewith. 
   According to an aspect of the present invention, there is provided an eraser dispenser including: a dispenser body formed with a storing chamber capable of storing therein an eraser that is longer than an overall length of the dispenser body; an external operation member which is provided in the dispenser body and is operated externally; and eraser-advancing means for extending the eraser from a distal opening of the dispenser body. 
   The present invention provides an effect of storing a relatively long eraser in the dispenser body, so that the stored eraser can be used for a long period of time without replacing with a new one. 
   The present invention provides an effect of storing a long eraser in various states in terms of its nature, which causes the dispenser body to be shaped freely, providing uniqueness for its design. 
   The prevent invention provides an effect of offering excellent operability by preventing the eraser that has been extended from retracting into the dispenser body due to a pressing force exerted on the paper surface or the like through the eraser during the use. 
   The present invention provides an effect of shaping the cross-section of an eraser to be stored freely compared with that of the stick-shaped eraser used in a conventional chuck-holding type dispenser, so that an eraser deformed in section can be used by allowing the section of a holding roller, chuck or the like to conform therewith. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and advantages of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings in which: 
       FIG. 1  is a front view of an eraser dispenser according to a first embodiment of the invention, with its cover removed; 
       FIG. 2  is a bottom view of the eraser dispenser with the cover put thereon; 
       FIG. 3  is a front view of a dispenser body of the eraser dispenser shown in  FIG. 1 ; 
       FIG. 4  is a back view of the cover shown in  FIG. 1 ; 
       FIG. 5  is a plan view of the cover of  FIG. 4 ; 
       FIG. 6  is a plan view of a driving roller shown in  FIG. 1 ; 
       FIG. 7  is a longitudinal cross-sectional view of the driving roller of  FIG. 6 ; 
       FIG. 8  is a front view of an arm shown in  FIG. 1 ; 
       FIG. 9  is a back view of the arm of  FIG. 8 ; 
       FIG. 10  is a plan view of the arm of  FIG. 8 ; 
       FIG. 11  is a right side view of the arm of  FIG. 8 ; 
       FIG. 12  is a left side view of the arm of  FIG. 8 ; 
       FIG. 13  is a longitudinal cross-sectional view of the arm of  FIG. 8 ; 
       FIG. 14  is a plan view of a rotary button shown  FIG. 1 ; 
       FIG. 15  is a longitudinal cross-sectional view of the rotary button of  FIG. 14 ; 
       FIG. 16  is a front view for assistance in explaining a state in which an anti-reverse turn stopper of the dispenser body is released; 
       FIG. 17  is a front view for assistance in explaining a rotary dispenser mechanism; 
       FIG. 18  is a front view for assistance in explaining a rotary dispenser mechanism; 
       FIG. 19  is a front view for assistance in explaining a rotary dispenser mechanism; 
       FIG. 20  is a view for illustrating a modification of the first embodiment in which the eraser is stored in an accordion-folded fashion; 
       FIG. 21  is a view for illustrating another modification of the first embodiment in which the eraser is stored at random; 
       FIG. 22  is a front view of a dispenser body according to a second embodiment of the present invention with its cover removed; 
       FIG. 23  is a view of the dispenser body of  FIG. 22  with an anti-reverse turn stopper released; 
       FIG. 24  is a front view of a side-knock type dispenser body of a third embodiment with its cover removed; 
       FIG. 25  is a plan view of the dispenser body of  FIG. 24 ; 
       FIG. 26  is a view of the dispenser body of  FIG. 24  with the anti-reverse turn stopper released; 
       FIG. 27  is a cross-sectional view of a slide operation type dispenser body according to a fourth embodiment; 
       FIG. 28  is a view of the dispenser body of  FIG. 27  in which the eraser is unwound to advance; 
       FIG. 29  is a cross-sectional view of a chuck-advance type dispenser body; 
       FIG. 30  is a view of the dispenser body of  FIG. 29  with its eraser unwound to advance; 
       FIG. 31  is a cross-sectional view of a chuck-advance type dispenser body according to a sixth embodiment; 
       FIG. 32  is a diagram of the dispenser body of  FIG. 31  with its eraser unwound to advance; 
       FIG. 33  is a front view of the eraser dispenser according to a seventh embodiment of this invention; and 
       FIG. 34  is a bottom view of the eraser dispenser of  FIG. 33 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention provides an eraser dispenser including a dispenser body and a cover put on the dispenser body. The dispenser body stores therein an eraser that is longer than the overall length of the dispenser body. The dispenser body is formed at its front end with an opening adapted to extend the eraser out. A guide means to assist in advancing the eraser is provided near the opening. A driving means for advancing the eraser through the guide means is provided in the dispenser body. An operation means for drivingly operating the driving means from the outside is provided in the dispenser body. An anti-reverse turn means having a stopper which locks the operation means is provided. 
   Embodiment 1 
     FIGS. 1 to 19  are views for illustrating an eraser dispenser according to a first embodiment of the present invention. Referring to  FIGS. 1 and 2 , the eraser dispenser includes a dispenser body  1  and a cover  3  put on the dispenser body  1 . The dispenser body  1  has a base  5  and an outer circumferential wall  2  extending from the base upward and surrounding the same. The dispenser body  1  is flat in a substantial gourd-shape. The outer circumferential wall  2  is formed in positions with mounting recesses  100  for mounting the cover  3  thereto. On the other hand, the cover  3  is formed with projections  31  at positions corresponding to the mounting recesses  100  so that it can be fitted to the dispenser body  1 . In addition, the cover  3  is formed with an oval bearing hole  32  adapted to receive an end of a fitting shaft  113  of a rotary button  11  to be described later. The oval bearing hole  32  is adapted to support a shaft  115  of the rotary button  11  for turning and displacement. 
   The dispenser body  1  has a tapered portion, which is formed at its front end with a distal opening  4 . An eraser to be described later is extended through this distal opening  4 . A pair of parallel guide walls  7  is provided adjacent to the distal opening  4 . The guide walls  7  define an eraser passageway  6  for directing the eraser to be advanced to the distal opening  4 . The rear portions of the guide walls  7  are formed in an expanded shape, defining a storing chamber  8  for storing the eraser in a spiral fashion. In other word, the storing chamber  8  is defined by storing-walls  9  connected to the guide walls  7 . 
   The cover  3  is formed with a protruding portion  10  protruding outwards. The disk-shaped rotary button  11  (external operation member) is provided for rotation in a space defined by the protruding portion  10 . As shown in  FIGS. 14 and 15 , the rotary button  11  is formed on its outer circumference with knurls  114  for easy rotary operation. A portion of the rotary button  11  is outwards protruded from the outer circumferential wall  2  so as to make it possible to operate the rotary button  11  externally. The knurls  114  are formed to advance the eraser and prevent the same from sliding. Needless to say, the knurls  114  may be shaped in a lattice pattern or in a rimple pattern such as circle or rectangle. 
   A small gear part  20  is disposed coaxially and integrally with the rotary button  11 . The rotary button  11  is formed in its side surface with a gear portion  112  (anti-reverse turning means), with which a detent  122  of an anti-reverse turning arm  12  is engaged. The anti-reverse turning arm  12  is to be described later. Preferably, part of the gear portion  112  adapted to prevent turning is formed to be inclined at an angle of, e.g., about 30 degrees. An attachment shaft  113  of the arm  12  is projected from the center of the rotary button  11 . Referring to  FIG. 3 , reference numerals  14  and  15  denote roller mounting portions for a driving roller  13  and a driven roller  17 , respectively. In addition, reference numeral  16  denotes a claw-like retainer, which is formed on the dispenser body  1  to retain the arm  12 . 
     FIGS. 8 to 13  illustrate the anti-reverse turning arm  12  in which its proximal pivotal part  121  is coupled to the detent  122  by way of a flexible part  123 . When the rotary button  11  is pushed inwards, the flexible part  123  is bent to release engagement of the detent  122 , so that the eraser can forcibly be retracted into the dispenser body  1  for storage. The detent  122  can be engaged with the gear portion  112  for anti-reverse turning. Incidentally, reference numeral  124  denotes a mounting hole adapted to mount the rotary button  11  to an arm-mounting portion. 
   The parallel guide walls  7  of the dispenser body  1  are provided with respective operation openings. The driving roller  13  having a pinion  131  is rotatably provided near one of the operation openings, that is, near a driving side operation opening. The driving roller  13  is brought into contact with a side of the eraser within the eraser passageway  6  to hold the same. The pinion  131  of the driving roller  13  is engaged with the small gear part  20  of the rotary button  11 . When the rotary button  11  is turned, the pinion  131  and the small gear part  20  cooperatively turn counterclockwise to advance the eraser. In this case, if the driving roller  13  is formed on its outer circumference with knurls to provide a frictional force, the eraser can be advanced steadily. Incidentally, in  FIG. 7 , reference numeral  133  denotes a portion fitted to the dispenser body  1 , whereas reference numeral  134  denotes a recess. However, the portion  133  and the recess  134  may be formed into a through hole. 
   On the other hand, a driven roller  17  (receiving member) is rotatably provided near the other of the operation openings, that is, near a driven side operation opening. The driven roller  17  is brought into contact with another side of the eraser within the eraser passageway  6  to hold the same. Incidentally, the driven roller  17  may have the same construction as that of the driving roller  13  as shown in  FIGS. 14 and 15  so long as it receives a pressing force of the driving roller  13  and directs the eraser. The driven roller  17  may be stationary. 
   A description will be made of an anti-reverse rotation mechanism for the rotary button  11  in relation to the arm  12  shown in  FIGS. 8 to 13 . The detent  122  formed on the arm  12  is engaged with the gear portion for anti-reverse turning formed on the rotary button  11  to thereby prevent the rotary button  11  from turning reversely. Specifically, since the detent  122  is received by the gear portion  112  formed in the lateral side of the rotary button  11 , the reverse turning can be prevented. On the other hand, the gear portion  112  is formed to be inclined in the direction of normal rotation, so that the detent  122  cannot be engaged with the gear portion  112 . Thus, the rotary button  11  can be turned while the arm  12  is being bent. When the eraser extended from the distal opening  4  is retracted into the dispenser body, pressing the rotary button  11  inward bends the flexible portion  123  of the arm  12  to disengage the detent  122  from the gear portion  112 , thereby releasing the engagement. 
   Referring to  FIGS. 17 to 19 , the operation of the eraser dispenser according to the embodiment will be described below.  FIGS. 17 to 19  illustrate transmission of the rotational force of the rotation-feeding mechanism, that is, advancement of the eraser. At first, extending of the eraser from the distal opening  4  of the dispenser body  1  is explained. 
   Turning the rotary button  11  as the larger gear clockwise makes the small gear part  20  integral with the rotary button  11  turn in the same direction as the rotary button  11  (see  FIG. 17 ). 
   Then, since gear teeth formed inside the small gear part  20  is engaged with corresponding gear teeth formed on the driving roller  13  for advancing the eraser, the driving roller  13  is turned in a direction opposite to the turning direction of the rotary button  11 . In other word, the driving roller  13  engaged with the small gear part  20  is forcibly turned counterclockwise (see  FIG. 18 ). Since a portion of the driving roller  13  projecting between the guide walls  7  is in contact with a side of the eraser, the eraser can be advanced forward along the guide walls  7 . 
   At this time, the turnable driven roller  17  faces the driving roller  13  so as to securely hold the eraser therebetween. Specifically, since a portion of the driven roller  17  projecting into the eraser passageway  6  presses the other side of the eraser, the clockwise turning of the driven roller  17  enables the eraser to securely advance in the eraser passageway  6  of the guide walls  7  and extend through the distal opening  4  (see  FIG. 19 ). 
   When the eraser is retracted into the dispenser body, the engagement of the detent  122  of the anti-reverse turning arm  12  with the gear portion  112  of the rotary button  11  is released. More specifically, the rotary button  11  is pressed toward inside the dispenser body through the operation-opening formed in the outer circumferential wall  2  to bend the arm  12  supporting the rotary button  11 . This disengages the gear portion  112  from the detent  122 , thereby causing the driving roller  13  holding the eraser to turn freely. Consequently, the portion of the eraser extended from the distal opening  4  can be retracted in the dispenser body by pressing the eraser thereinto. 
   Incidentally,  FIGS. 20 and 21  show eraser-stored states according to modifications of the first embodiment;  FIG. 20  shows a state in which the rear portion of the eraser is stored in the storing chamber  8  in an accordion fashion; and  FIG. 21  shows another state in which the rear portion of the eraser is stored in a random fashion. 
   Embodiment 2 
     FIGS. 22 and 23  show an eraser dispenser according to a second embodiment. In this embodiment, the teeth of a small gear part  20  formed integrally and coaxially with a rotary button  11  are in direct contact with a side of the eraser. The rotary button  11  advances the eraser in cooperation with a receiver arm  18  extending from an outer circumferential wall  2  of a dispenser body, and a rolling element  19 . A stopper bar  22  extending from the front of the dispenser body toward the rear is engaged with the small gear part  20  of the rotary button  11 . As shown in  FIG. 23 , the rotary button  11  is pressed innermostly and displaced inward, which releases the engagement of the stopper bar  22  with a gear portion  112 , whereby the rotary button  11  can be turned reversely. Thus, the eraser can be retracted. 
   In this embodiment, the eraser is wound about a core  24  in a storing chamber  8  of the dispenser body  1 . This embodiment does not include the driving roller  13  as shown in the first embodiment. Instead, the small gear part  20  of the rotary button  11  serves as an eraser advance means, which is in direct contact with the eraser so as to advance it. The receiving arm  18  is extended forward from the outer circumferential wall  2  and is urged inward. The receiving arm  18  is provided at its distal end with the rolling element  19  as a receiving member, which faces the small gear part  20 . 
   The stopper bar  22  is extended rearward from the outer circumferential wall. The distal end of the stopper bar  22  is engaged with the small gear part  20  of the rotary button  11   50  as to prevent the rotary button  11  from turning reversely (see  FIG. 22 ). When the rotary button  11  is pressed inward against the urging force of the arm  18 , the shaft of the rotary button  11  is displaced inward in an oval bearing hole  32 . Consequently, the stopper bar  22  is disengaged from the small gear part  20 , which makes it possible to turn the rotary button  11  reversely. Thus, the eraser can be retracted in the dispenser body with ease while the rotary button is idled. 
   Embodiment 3 
     FIGS. 24 to 26  show a side knock operation type eraser dispenser according to a third embodiment of the invention. This eraser dispenser does not include the core  24  for the eraser as shown in the second embodiment. The eraser of this embodiment is stored in a spiral manner as with the first embodiment. In this embodiment, a side knock button  21  has such high resiliency as to be flexible. Reference numeral  23  in the figures denotes a projection adapted to push the stopper bar  22 . 
     FIG. 25  is an assemble view of the side knock type eraser dispenser, in which the side knock button  21  is being pressed. The side knock button  21  is formed its distal end with a saw-tooth-like portion. When this saw-tooth-like portion pushes a corresponding saw-tooth-like portion formed in a small gear portion  131  of a driving roller  13 , the driving roller  13  is turned. Further pushing the corresponding saw-tooth-like portion causes the saw-tooth-like portion of the side knock button  21  to disengage from the corresponding saw-tooth-like portion, so that the driving roller  13  can be made reversely turnable by pushing an anti-reverse turn bar. 
   More specifically, the side knock button  21  is disposed in the operation opening of the outer circumferential wall  2  in such a manner as to be pressable inward. The distal end of the knock button  21  is engaged with the small gear portion of the driving roller  13 . The knock button  21  is depressed by the knocking operation to thereby turn the small gear portion counterclockwise. That is, the driving roller  13  is turned counterclockwise, which advances the eraser. A driven roller  17  is disposed to face the driving roller  13  with the eraser held therebetween. The driving roller  13  and the driven roller  17  cooperate to advance the eraser. Thus, pressing the knock button  21  can advance the eraser. 
   The eraser can be used to erase characters, etc. written on a paper surface by pressing it against the paper surface. The driving roller  13  is prevented from being reversely turned by anti-reverse turn stopper; therefore, the eraser is not been retracted into the dispenser body during the use of it, that is, it does not become unserviceable. On the other hand, when the eraser is retracted, the knock button  21  is pressed innermostly to disengage the anti-reverse turn stopper from the driving roller  13 . Thus, the eraser can be pressed into the dispenser body with ease. 
   Embodiment 4 
     FIGS. 27 and 28  show a slide operation type eraser dispenser according to a fourth embodiment of the present invention. A sliding button  25  is disposed in an opening of an outer circumferential wall  2  of the dispenser body  1 . This sliding button  25  has a resilient leg  251 , which constantly urges the sliding button  25  toward the outside of the dispenser body. In addition, the sliding button  25  is provided at its front portion with a spring receiver  26  with a spring  27  disposed therebetween. The sliding button  25  is constantly urged backward by the spring  27 . 
   In addition, a receiving member  28  is provided opposite to the sliding button  25  with the eraser held therebetween. The receiving member  28  has a resilient portion that is in contact with the eraser, in order to prevent the eraser from retracting. Further, the resilient portion is formed like saw-teeth not only to facilitate advancement of the eraser but also to prevent the eraser from moving backward. In the figures, reference numeral  102  denotes an eraser fitting rib or a guide means formed near the distal opening. 
     FIG. 28  illustrates a state in which the slide button  25  is depressed inward and slid forward to advance the eraser wound around a core  24 . In this case, the saw-teeth-like portion, of the sliding button  25 , in contact with the eraser is formed such that it facilitates the advancement of the eraser due to more frictional contact when the eraser is advanced whereas it facilitates the slide of the eraser due to less frictional contact when the eraser is retracted. 
   Embodiment 5 
     FIGS. 29 and 30  depict a chuck advance type eraser dispenser according to a fifth embodiment of the present invention. By operating a knock button  21 , an eraser is advanced by use of a chuck mechanism as an eraser advance means. The eraser is longer than the overall length of a dispenser body and is wound around a core  24 .  FIG. 29  illustrates a state in which a holding chuck  29  is closed to hold the eraser. The knock button  21  is disposed for pivotal movement in an opening of the outer circumferential wall  2  of the dispenser body  1 . A front corner portion of the knock button  21  is in contact with the inclined part  291  of a chuck  29 , which is provided in the dispenser body  1  for slidable movement. Note that the inclined face of the inclined part  291  is formed to descend backward. In addition, the inclined part  291  may be formed differently from the chuck  29 . 
   The chuck  29  is formed with a flat receiving part  292 , which faces the inclined part  291  with the eraser interposed therebetween. A supporting portion  101  is coupled to the outer circumferential wall  2  to hold the proximal part of the chuck  29 . The flat receiving part  292  is guided along the guide surface  101   a  of the supporting portion  101 , so that the chuck  29  can slide smoothly. 
   A spring  27  is disposed between the front upright wall of the slope part  291  and a receiving member  26  so as to constantly urge the chuck  29  backward. A chuck ring  30  is loosely fitted to a distal end of the chuck ring  30 . The chuck ring  30  is formed at its front edge with a flange  301 . This flange  301  is normally engaged with a step formed on the inner circumference of the spring receiver  26  by the elastic force of the spring  27 . A spring receiver  26  is formed at its front edge with an inner flange  261 , which serves as a stopper for the flange  301  of the chuck ring  30 . 
     FIG. 30  depicts a state in which the knock button  21  is depressed to extend the eraser from the distal opening  4 . As shown in the figure, the knock button  21  is depressed to thereby allow the front corner portion thereof to descend along the inclined face of the inclined part  291 , which advances the chuck  29  together with the eraser against the backward elastic force of the spring  27 . In the course of the advance of the chuck  29 , also the chuck ring  30  is advanced together with the eraser; however, the flange  301  of the chuck ring  30  comes into contact with the inner flange  261  of the spring receiver  26  for engagement. As a result, the chuck ring  30  disengages from the chuck  29 , whereby the chuck  29  is opened so as not to hold the eraser. Thereafter, pressing the knock button is released to move the chuck  29  to its initial position where the chuck  29  holds the eraser. In this state, the eraser can be used because it is held by the chuck  29  so as not to retract into the dispenser body. 
   Embodiment 6 
     FIGS. 31 and 32  depict a chuck type eraser dispenser according to a sixth embodiment of the present invention. In this embodiment, an edge of the distal opening  4  of a dispenser body  1  is used as a part for engaging with a chuck ring  30  to open and close a chuck  29 . A spring  27  urging the chuck  29  backward is disposed between a spring receiver  26  formed on the outer circumferential wall  2  of the dispenser body  1  and a front upright wall of an inclined part  291  of the chuck  29 . A rear end flange  302  of the chuck ring  30  is engaged with the front of a spring receiver  26  to close the chuck  29 . 
     FIG. 32  illustrates a state in which a knock button  21  is depressed to advance an eraser. While the chuck  29  is moved forward, the rear end flange  302  of the chuck ring  30  is engaged with the inner surface of the distal opening  4  so as to open the chuck  29 . 
   Embodiment 7 
     FIGS. 33 and 34  show a seventh embodiment of this invention, in which there is provided at the rear portion of the dispenser a block shaped rubber eraser  40  for erasing large letters in addition to the eraser provided at the front portion thereof for erasing small letters. 
   While the above embodiments of the invention describe the eraser dispenser, they are applicable to other dispensers for advancing a flexible elongate object such as a plastic pencil. An anti-reverse turn mechanism serving as a retracting-prevention means which functions to prevent the eraser from retracting during the use of it may be configured to release its function with an operation member depressed, or not depressed in a normal state. In the latter case, it is to be noted that if the eraser is used, the anti-reverse turn mechanism is used with the operation member depressed. 
   Further, the eraser dispenser of the present invention may be a disposable single piece or may have a removable cover. In addition, the eraser dispenser may be formed to have a storing chamber of the dispenser body as an independent one. More specifically, the eraser dispenser may have a combination of an eraser storing unit and a main unit incorporating the advancing mechanism. In this case, the eraser can be replaced with a new one by a single operation. 
   While the invention has been described in its preferred embodiments, it is to be understood that the words which have been used are words of description rather than limitation and that changes within the purview of the appended claims may be made without departing from the true scope and spirit of the invention in its broader aspects.