Patent Publication Number: US-8978731-B2

Title: Stationery tool with a pushbutton having a push-proof capability

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a stationery tool, and more particularly to a stationery tool with a pushbutton having a push-proof capability. 
     2. Description of Related Art 
     A stationery tool, such as a correction tape, a thin film dispenser, a writing tool or a rubber, usually has an extension mechanism to push a working element to extend out of a body of the stationery tool. Accordingly, a user can carry out office work, such as thin film coating, writing or error erasing with the extending working element. One kind of conventional extension mechanism comprises a pushbutton to extend or retract a working element out of or into a body of a stationery tool reciprocatingly when the pushbutton is pushed. 
     However, the conventional pushbutton does not have a push-proof capability, so the conventional pushbutton will be pushed carelessly or unintentionally to cause the working element to extend out of a body arbitrarily. Particularly, a stationery tool having a pushbutton is often put in a briefcase or an outfit pocket, so the working element of the stationery tool may be unintentionally pushed to extend out of the body of the stationery tool due to being compressed. Consequently, the documents in the briefcase or the outfit pocket are easily dirtied to cause inconvenience in use or even irretrievable damage. 
     To overcome the shortcomings, the present invention tends to provide a stationery tool to mitigate or obviate the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     The main objective of the invention is to provide a stationery tool with a pushbutton having a push-proof capability to keep the pushbutton from being pushed unintentionally. 
     The stationery tool has a body, a pushbutton, a working element, and a push-proof device. The pushbutton is pushably and rotatably mounted on an end of the body. The working element is mounted in the body and is connected to and driven by the pushbutton. The push-proof device is mounted between the body and the pushbutton and has a blocking protrusion and a blocking segment. The blocking protrusion is disposed on the pushbutton. The blocking segment is disposed on the body, selectively abuts the blocking protrusion and has a passage defined in the blocking segment to allow the blocking protrusion to pass. 
     Accordingly, the pushbutton can be rotated to make the blocking protrusion abut the blocking segment, such that the pushbutton can be kept from being pushed relative to the body and can be kept in a locked condition. Consequently, the working element can be kept from extending out of the body unintentionally to dirty or damage other objects, such that the utility of the stationery tool in accordance with the present is improved. 
     Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a first embodiment of a stationery tool in accordance with the present invention; 
         FIG. 2  is an enlarged perspective view of a pushbutton of the stationery tool in  FIG. 1 ; 
         FIG. 3  is an enlarged perspective view in partial section of the stationery tool in  FIG. 1 ; 
         FIG. 4  is an enlarged side view in partial section of the stationery tool in  FIG. 1 ; 
         FIG. 5  is an end view in partial section of the stationery tool along line  5 - 5  in  FIG. 4 ; 
         FIG. 6  is an enlarged operational perspective view of the stationery tool in  FIG. 1  showing the pushbutton in an unlocked condition; 
         FIG. 7  is an enlarged operational perspective view of the stationery tool in  FIG. 1  showing the pushbutton in a locked condition; 
         FIG. 8  is a perspective view of a pushbutton of a second embodiment of a stationery tool in accordance with the present invention; 
         FIG. 9  is an operational perspective view of the second embodiment of the stationery tool in accordance with the present invention showing the pushbutton in an unlocked condition; 
         FIG. 10  is a cross sectional end view of the stationery tool along the line  10 - 10  in  FIG. 9  showing the pushbutton in an unlocked condition; and 
         FIG. 11  is an operational perspective view of the second embodiment of the stationery tool in  FIG. 9  showing the pushbutton in a locked condition. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     A stationery tool in accordance with the present invention has a pushbutton having a push-proof capability, may be a writing tool, a rubber or a thin film dispenser and may be any stationery tool having a pushbutton for pushing a working element out of a body for proceeding with office work. The stationery tool comprises a body, a pushbutton, a working element and a push-proof device. The pushbutton is pushably and rotatably mounted on an end of the body. The working element is mounted in the body and is connected to and driven by the pushbutton. When the pushbutton is pushed, the working element extends out of the body to enable a user to proceed with office work. The working element may be a refill, a rubber, a correction tape, a thin film dispensing unit or the like. The body, the pushbutton and the working element may have different shapes, structures and connections and may be conventional, and therefore the detail descriptions about the body, the pushbutton and the working element are omitted. A thin film dispenser serves as a figure example for describing the present invention. 
     With reference to  FIGS. 1 to 5 , the push-proof device is mounted between a body  10  and a pushbutton  12  and comprises a blocking protrusion and a blocking segment  30 . The blocking protrusion is formed on the pushbutton  12 . The blocking segment  30  is formed on an inner surface of the body  10 . The blocking protrusion comprises at least one blocking tab  20 , and preferably two blocking tabs  20  are implemented. The blocking tabs  20  are formed respectively on two ends of a diameter of the pushbutton  12 . Each blocking tab  20  is axially formed on and protrudes from the pushbutton  12  at an end that extends into the body  10  and has a compressible elasticity relative to the pushbutton  12 . Each blocking tab  20  has a positioning rib  22  formed on an outer surface of the blocking tab  20 . The blocking segment  30  is formed on the inner surface of the body  10  and comprises a blocking flange being perpendicular to the inner surface of the body  10  and a passage defined in the blocking segment  30  to allow the blocking protrusion to pass. The passage comprises at least one guiding channel  32  defined through the blocking segment  30  and selectively aligning respectively with the at least one blocking tab  20 . Preferably, two guiding channels  32  are implemented to fit with the number of the blocking tabs  20  and are spaced from each other at 180° in curvature. In addition, the body  10  may further have at least one positioning groove  34  formed in an inner surface of the body  10 . Preferably, two positioning grooves  34  are implemented to fit with the number of the blocking tabs  20  and are formed in the inner surface of the body  10  at positions beside the passage. With reference to  FIG. 5 , the two positioning grooves  34  are spaced from each other at 180° in curvature, and each positioning groove  34  is spaced from an adjacent one of the guiding channels  32  at 90° in curvature. In addition, the body  10  may further have at least one positioning channel  36  formed in the inner surface of the body  10  and respectively corresponding to the at least one guiding channel  32 . Preferably, the at least one positioning channel  36  respectively aligns and communicates with the at least one guiding channel  32 . Consequently, the positioning rib  22  on the at least one blocking tab  20  respectively engages the at least one positioning channel  36  when the at least one blocking tab  20  respectively aligns with the at least one guiding channel  32 . Preferably, two positioning channels  36  are implemented to fit with the numbers of the blocking tabs  20  and the guiding channels  32 . 
     With such an arrangement, with reference to  FIGS. 1 ,  3 ,  5  and  6 , when the blocking tabs  20  on the pushbutton  12  align respectively with the guiding channels  32  in the body  10 , the pushbutton  12  is pushable. When the pushbutton  12  is pushed, the blocking tabs  20  can extend into the guiding channels  32 , such that the pushbutton  12  can be pushed to extend into the body  10  and to drive the working element  14  to extend out of the body  10 . Consequently, the stationery tool can be applied to proceed with the desired office work. At this time, because the blocking tabs  20  extend respectively into the guiding channels  32 , the pushbutton  12  can be kept from rotating relative to the body  10 . In addition, before the pushbutton  12  is pushed, the positioning ribs  22  on the blocking tabs  20  respectively engage the positioning channels  36 . With the engagement between the positioning ribs  22  and the positioning channels  36 , a guiding effect is provided to enable a user to push the pushbutton  12  smoothly, and the pushbutton  12  can be kept from rotating relative to the body  10  arbitrarily. Accordingly, the pushbutton  12  can be kept in the pushable condition stably. 
     To lock the pushbutton  12 , with reference to  FIGS. 1 ,  5  and  7 , the pushbutton  12  is forced to rotate relative to the body  10 , and the positioning ribs  22  are disengaged from the positioning channels  36  with the compressible elasticity of the blocking tabs  20 . After the pushbutton  12  is rotated by an angle to make the blocking tabs  20  or the positioning ribs  22  face the blocking segment  30 , the pushbutton  12  is not pushable and cannot be pushed to extend into the body  10  due to the abutment between the blocking segment  30  and the blocking tabs  20  or the positioning ribs  22 . Consequently, the pushbutton  12  is locked. With the pushbutton  12  being locked, the pushbutton  12  is not pushable and the working element  14  will not extend out of the body  10  unintentionally, thereby preventing the working element  14  from dirtying or damaging other objects. 
     In addition, when the pushbutton  12  is rotated relative to the body  10  by a predetermined angle, such as 90°, the positioning ribs  22  on the blocking tab  20  will respectively engage the positioning grooves  34  in the body  10 . Accordingly, the pushbutton  12  can be held in the locked condition and will not be arbitrarily rotated back to the unlocked condition where the blocking tabs  20  align with the guiding channels  32 . Thus, the pushbutton  12  can be prevented from being unlocked unintentionally. 
     To unlock the pushbutton  12 , the pushbutton  12  is rotated in reverse. With the compressible elasticity of the blocking tabs  20 , the blocking tabs  20  can be compressed to disengage the positioning ribs  22  on the blocking tabs  20  from the positioning grooves  34  and to make the pushbutton  12  rotatable relative to the body  10 . When the pushbutton  12  is rotated to a position where the blocking tabs  20  align with the guiding channels  32 , the pushbutton  12  is unlocked and pushable so that the stationery tool is under the operation condition. Alternatively, the pushbutton  12  can be unlocked by rotating the pushbutton  12  continuously in a single direction along which the pushbutton  12  can be rotated to lock. 
     With reference to  FIGS. 8 to 10 , in the second embodiment of the push-proof device, the blocking protrusion comprises at least one blocking rib  50  formed on and protruding from the outer surface of the pushbutton  42 . The blocking segment  60  is formed on the end of the body  40 , and a passage is formed through the blocking segment  60  to allow the blocking rib  50  to pass the blocking segment  60  and to extend into the body  40 . The passage comprises at least one guiding channel  62  axially defined in the end of and extending into the body  40  and selectively aligning respectively with the at least one blocking rib  50 . 
     With such an arrangement, while the pushbutton  42  is at a position where the blocking rib  50  aligns with the guiding channel  62 , the pushbutton  42  is pushable and can be pushed to extend into the body  40 . When the pushbutton  42  is pushed, the blocking rib  50  extends into and slides relative to the guiding channel  62  and the working element is driven to extend out of the body  40  to proceed with the desired office work. In addition, the guiding channel  62  can provide a limiting effect to the blocking rib  50  to keep the pushbutton  42  from rotating relative to the body  40 . 
     To lock the pushbutton  42 , with reference to  FIGS. 10 and 11 , the pushbutton  42  is rotated relative to the body  40  to move the blocking rib  50  away form the position where the blocking rib  50  aligns with the guiding channel  62 . Consequently, the blocking rib  50  will face and abut the blocking segment  60  on the end of the body  40 . With the abutment between the blocking rib  50  and the blocking segment  60 , the pushbutton  42  is not pushable and is locked. Accordingly, the working element will not extend out of the body  40  unintentionally to dirty or damage other objects. 
     In addition, with reference to  FIGS. 8 to 10 , the pushbutton  42  has a positioning segment  52  axially formed on and protruding from an end of the pushbutton  42  and having a thickness smaller than that of the pushbutton  42 . At least one positioning rib  54  is formed on the outer surface of the positioning segment  52 . The body  40  has at least one positioning groove  64  formed in the inner surface of the body  40  and selectively and respectively engaging the at least one positioning rib  54 . Preferably, the number of the positioning rib  54 , the guiding channel  62  and the positioning groove  64  is one, respectively. Furthermore, the body  40  may further have a positioning channel  66  formed in the inner surface of the body  40  and selectively engaging the positioning rib  54 . The positioning groove  64  is spaced from the positioning channel  66  at 90° in curvature. Accordingly, with the engagement of the positioning rib  54  with the positioning channel  66  or the positioning groove  64 , a force is necessary to disengage the positioning rib  54  from the positioning channel  66  or the positioning groove  64  for rotating the pushbutton  42  relative to the body  40 . Otherwise, the pushbutton  42  cannot be rotated relative to the body  40  arbitrarily. 
     When the pushbutton  42  is in the unlocked condition where the blocking rib  50  aligns with the guiding channel  62 , the positioning rib  54  engages the positioning channel  66 . With the engagement between the positioning rib  54  and the positioning channel  66 , the pushbutton  42  can be held in the unlocked condition. When the pushbutton  42  is rotated by a predetermined angle to lock the pushbutton  42 , such as 90° as aforementioned, the positioning rib  54  engages the positioning groove  64 . With the engagement between the positioning rib  54  and the positioning groove  64 , the pushbutton  42  can be held in the locked condition. Accordingly, the pushbutton  42  is kept from rotating relative to the body  40  arbitrarily, such that the conditions of the pushbutton  42  will not be changed unintentionally. Moreover, because the positioning segment  52  has a thickness smaller than that of the pushbutton  42 , a compressible elasticity is provided to the positioning segment  52  relative to the pushbutton  42 . Thus, the positioning rib  54  on the positioning segment  52  can engage and disengage from the positioning groove  64  or the positioning channel  66  conveniently. 
     Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.