Abstract:
An upper and a lower rubber plug holders are provided with fixed arms to be inserted and held in upper and lower fixed blocks, and operatively pushed parts at ends of the fixed arms. The upper and lower fixed blocks are provided with slots in which the fixed arms are inserted and held and from which the operatively pushed parts are protruded on the side opposite to the insertion side. The slots are provided with balls and coil springs which fix the fixed arms inserted into the slots by the insertion of the fixed arms into the slots and allow the fixed arms to be pulled out of the slots by a push of the operatively pushed parts. This structure shortens time to change the parts and ensures easy and positive change of the parts.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a rubber plug fitting apparatus for fitting a rubber plug over a wire end. 
     2. Description of the Related Art 
     A known conventional rubber plug fitting apparatus is disclosed in a Japanese Patent Application, Laid-Open Publication No. Hei-9-260008. This rubber plug fitting apparatus has a rubber plug supply section, a rubber plug receiving section and a rubber plug fitting section. The rubber plug supply section serves to align rubber plugs to sequentially feed them to the rubber plug receiving section. The rubber plug receiving section serves to transport the rubber plugs supplied from the rubber plug supply section to the rubber plug fitting section. The rubber plug fitting section holds a rubber plug with an opposed rubber plug holder pair and brings the rubber plug close to a wire end held separately to fit the rubber plug over the wire end. 
     As shown in FIG. 1, the rubber plug fitting section has a pair of rubber plug holders  1 ,  1  each screwed to supporting blocks  2 ,  2 . The rubber plug holders  1 ,  1  each have recesses  4 ,  4  in the opposed surfaces for accommodating a rubber plug. The rubber plug fitting section also has a pair of insertion guides  6 ,  6  screwed to a pair of insertion guide supporting blocks  5 ,  5  as shown in FIG.  1 . The insertion guides  6 ,  6  have insertion pipe halves  7 ,  7  in a protruding manner, a pipe being divided along the central axis thereof. The insertion pipe halves  7 ,  7  are joined to constitute a pipe to be inserted into a tubular hole of a rubber plug  3 . 
     The insertion guide supporting blocks  5 ,  5  are provided to be movable with respect to the holder supporting blocks  2 ,  2  so as to insert the insertion pipe halves  7 ,  7  into the tubular hole of the rubber plug  3  held between the rubber plug holders  1 ,  1 . The pipe formed with the joined insertion pipe halves  7 ,  7  serves to secure a wire insertion space in the rubber plug  3 . In this rubber plug fitting apparatus, the rubber plug holders  1 ,  1  and the insertion guides  6 ,  6  are changed in accordance with a kind or size of the rubber plug to be fitted, thereby to handle various kinds of rubber plugs. 
     However, in the above conventional rubber plug fitting apparatus, the rubber plug holders  1 ,  1  are screwed to the holder supporting blocks  2 ,  2  and the insertion guides  6 ,  6  are screwed to the insertion guide supporting blocks  5 ,  5 , which arrangement requires much time to change the parts and skills of adjusting the degree of screwing or the like. Thus every time the size or kind of the rubber plug  3  is changed, the operation of the apparatus is entirely suspended for a long time, which prevents reduction in cost of fitting rubber plugs. 
     SUMMARY OF THE INVENTION 
     This invention has been achieved with such points in mind. 
     It is therefore an object of the invention to provide a rubber plug fitting apparatus which takes short time to change parts and provide easy and positive change of the parts. 
     According to a first aspect of the invention, there is provided a rubber plug fitting apparatus which comprises a rubber plug holder for holding a rubber plug to be fitted over a wire end, and a holder supporting block to which the rubber plug holder is detachably attached, the rubber plug holder comprising a fixed arm configured to be inserted and fixed into the holder supporting block, and an operatively pushed part formed at an end of the fixed arm, and the holder supporting block comprising a slot into which the fixed arm is inserted and fitted and from which the operatively pushed part is protruded on the side opposite to the insertion side, and 
     a fixing means for fixing the fixed arm inserted and fitted into the slot with the insertion of the fixed arm into the slot, and allowing the fixed arm to be pulled out of the slot at a press of the operatively pushed part. 
     Thus in this invention, the operatively pushed part and the fixed arm of the rubber plug holder are inserted into the holder supporting block to fix the fixed arm into the holder supporting block. At that time, the operatively pushed part is protruded from the slot of the holder supporting block on the side opposite to the insertion side. The fixing means fixing the fixed arm to the holder supporting block is set to allow the fixed arm to be pulled out of the slot by a push of the operatively pushed part protruded from the side opposite to the insertion side of the slot. 
     Thus in this structure, in order to detach the rubber plug holder from the holder supporting block, the operatively pushed part is pushed instead of pulling out the rubber plug holder, which improves the workability. More specifically, if the part of the rubber plug holder positioned on the insertion side of the holder supporting block is gripped to be pulled out, the rubber plug holder should be held on both sides, which provides low workability. In this structure, only a push of the operatively pushed part can easily detach the rubber plug holder from the holder supporting block. 
     According to a second aspect of the invention, the fixing means comprises a ball provided in an internal wall of the slot and arranged to be engaged with the fixed arm inserted and fitted into the slot, and a biasing means for biasing the ball to the slot side to engage the ball with the fixed arm inserted and fitted into the slot. 
     Thus in this invention, the ball provided in the internal wall of the slot of the holder supporting block presses the fixed arm with the biasing means, thereby to fix the rubber plug holder to the holder supporting block positively, providing a tactile feel. Thus the attachment/detachment of the rubber plug holder to/from the holder supporting block is easily performed. 
     More specifically, when the fixed arm of the rubber plug holder is inserted in the slot, the fixed arm of the rubber plug holder is pushed against the pressing force of the ball by confirming a click touch or a click feeling, thereby being pressed and fixed by the ball. On the other hand, when the fixed arm being removed, the operatively pushed part is pushed against the biasing force of the ball to push the ball up, thereby to detach the rubber plug holder easily. 
     According to a third aspect of the invention, the fixed arm is provided with a recess with which the ball is engaged. 
     According to a fourth aspect of the invention, the recess is a V-shaped groove. 
     Thus in this invention, the engagement of the ball with the recess formed in the fixed arm inserted into the slot fixes the rubber plug holder, and the disengagement of the ball with the recess by a push of the operatively pushed part removes the rubber plug holder. The so-called plunger mechanism provides speedy and positive attachment/detachment of the rubber plug holder, eliminating a cumbersome task such as screwing, and requiring no special skills. 
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
     The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in conjunction with the accompanying drawings, in which: 
     FIG. 1 is an exploded perspective view of a conventional rubber plug fitting section; 
     FIG. 2 is a front view of a rubber plug fitting apparatus according to an embodiment of this invention; 
     FIG. 3 is a plan view of the rubber plug fitting apparatus in this embodiment; 
     FIG. 4 is a perspective view of a rubber plug transfer section in this embodiment; 
     FIG. 5A is a front view showing a main part of a rubber plug pusher in this embodiment, and 
     FIG. 5B is a sectional view taken along line VB—VB in FIG. 5A; 
     FIG. 6A is a front view showing a positional relationship between the rubber plug transfer section and a rubber plug fitting section in this embodiment; 
     FIG. 6B is a plan view of FIG. 6A; 
     FIG. 7 is an exploded perspective view of the rubber plug fitting section in this embodiment; 
     FIG. 8 is an exploded perspective view of the rubber plug fitting section in this embodiment taken from a different angle from that of FIG. 7; 
     FIG. 9A is a section-in-part explanatory view showing the rubber plug fitting section before assemblage in this embodiment; and 
     FIG. 9B is a sectional explanatory view showing an assembled state of FIG.  9 A. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference to the accompanying drawings, a preferred embodiment of this invention will now be described. 
     As shown in FIGS. 2 and 3, a rubber plug fitting apparatus  10  consists generally of a rubber plug supply section  11 , a rubber plug transfer section  12  and a rubber plug fitting section  13  all of which are provided on a substrate B. 
     Rubber Plug Supply Section 
     The rubber plug supply section has a drum  15  for accommodating a plurality of rubber plugs  14  and a feeder  16  for aligning in a row the rubber plugs  14  supplied from the drum  15  to feed them to the rubber plug transfer section  12 . In the rubber plug supply section  11 , the drum  15  is rotationally moved to drop the rubber plugs  14  in the drum  15  into an alignment groove  16 A of the feeder  16 , thereby to push the rubber plugs  14  sequentially into the rubber plug transfer section  12 . 
     Rubber Plug Transfer Section 
     As shown in FIG. 4, the rubber plug transfer section  12  has a rubber plug pusher  17  arranged at an end of the feeder  16  (the end positioned on the downstream side of the flow of the rubber plugs  14 ) and a rotary transporter  18  disposed above the rubber plug pusher  17 . 
     Now the structure of the rubber plug pusher  17  will be described with reference to the drawings. As shown in FIG. 5B, the rubber plug pusher  17  has an escape base  20  with a pin insertion space  19  penetrating inside in the vertical direction, an escape pin  21  fitted movably in the vertical direction in the pin insertion space  19  and a rubber plug holder  22  formed in the upper part of the pin insertion space  19 . 
     The rubber plug holder  22  is a space communicated with the alignment groove  16 A of the feeder  16 . A rubber plug  14  reaching the holder  22  is pushed by the escape pin  21  to the rotary transporter  18 . The escape pin  21  has at its front end a transporting pin insertion recess  21 A as shown in FIG.  5 B. 
     At the bottom of the escape pin  21  integrally formed is a large-diameter part  23  which is movable up and down in the pin insertion space  19  while defining the stroke of up and down movement of the escape pin  21 . At the bottom of the large-diameter part  23  integrally formed is a flange  24  with a diameter larger than that of the large-diameter part  23 , which flange is movable up and down with the large-diameter part  23  in the pin insertion space  19 . 
     At the bottom of the flange  24  integrally formed is a piston rod  25  extended downwardly therefrom. The lower part of the piston rod  25  is introduced into a jig cylinder not shown and driven to move up and down with the cylinder. 
     On the flange  24 , a coil spring  26  is arranged in a compressed state to surround the large-diameter part  23  and the escape pin  21 . The upper end of the coil spring  26  abuts against an upper end  19 A of the pin insertion space  19 . Thus the flange  24  is biased downwardly with the coil spring  26 . 
     Now the structure of the rotary transporter  18  constituting the rubber plug transfer section  12  with the rubber plug pusher  17  will be described with reference to the drawings. 
     As shown in FIGS. 6A and 6B, the rotary transporter  18  has a rotating shaft  27  arranged above the rubber plug pusher  17  along the horizontal direction, a rotation block  28  fixed to the rotating shaft  27  and four transporting pins  29  fixed around the rotation block  28  to form the right angle with the adjoining pins. 
     As shown in FIG. 4, the rotating shaft  27  is extended laterally to support thereon a transmission pulley  30  for receiving the transmission of a rotational driving force. Further, as shown in the same figure, a driving shaft  31  is arranged in parallel with the rotating shaft  27  at the lower part of the apparatus. The driving shaft  31  rotatably supports a drive pulley  32  thereon. On the transmission pulley  30  and the drive pulley  32 , an endless belt  33  is wound. The driving shaft  31  is set to rotate so as to rotate the rotating shaft  27 , 90 degrees at a time. The rotational timing depends on the movement in the rubber plug fitting section  13  described later. The rotational direction of the transporting pins  29  is a clock-wise direction in FIG.  2 . The transporting pin  29  receiving the rubber plug  14  from the rubber plug pusher  17  rotates 90 degrees to supply the rubber plug  14  to the rubber plug fitting section  13  described later. 
     Rubber Plug Fitting Section 
     Now with reference to FIGS. 7 to  9 B, the structure of the rubber plug fitting section  13  will be described. The rubber plug fitting section  13  in this embodiment has an upper holder supporting block  34  and a lower holder supporting block  35  used in a pair, which blocks  34  and  35  are provided on the apparatus body side and movable in both the vertical and fitting transverse directions, and an upper rubber plug holder  36 , a lower rubber plug holder  37 , an upper insertion guide  38 , and a lower insertion guide  39 , which holders and guides being fitted and fixed to the upper and lower holder supporting blocks  34  and  35 , respectively. 
     As shown in FIG. 7, the upper holder supporting block  34  has an upper fixed block  40  to which the upper rubber plug holder  36  is attached and an upper movable block  41  positioned closer to the rotary transporter  18  than the upper fixed block  40 . 
     The upper fixed block  40  has a slot  40 A penetrating along the apparatus-width direction. The upper movable block  41  also has a slot  41 A penetrating in the same direction. The upper movable block  41  is arranged to reciprocatingly slide on guide rods  42 ,  42  laid across the opposed surfaces of the upper fixed block  40  and the upper holder supporting block  34 . The upper movable block  41  is driven with a drive means not shown to move reciprocatingly along the guide rods  42 ,  42  in a prescribed timing. 
     As shown in FIG. 9A, the slot  40 A has an internal wall in which provided is a ball  44  that is biased with a coil spring  43  as a biasing means to be protruded but not pushed out into the slot  40 A. In short, the spring coil  43  and the boll  44  constitute a so-called ball plunger. Such a ball plunger is, not shown in the figure, provided in the slot  41 A of the upper movable block  41  in the same manner. 
     Now the structure of the upper rubber plug holder  36  to be fitted into the slot  40 A of the upper fixed block  40  will be described. The upper rubber plug holder  36  consists of a rubber plug holding block  46  having a rubber plug accommodating recess  45  at its bottom surface for accommodating the upper half of the rubber plug  14  (divided along the plane passing through the axis of rotation of the rubber plug  14 ), a fixed arm  47  integrally formed at a side of the rubber plug holding block  46  and an operatively pushed part  48  integrally formed at an end of the fixed arm  47 . The fixed arm  47  and the operatively pushed part  48  are integrally formed so as to extend generally in line with their total length set to be longer than the length of the slot  40 A. The fixed arm  47  has a V-shaped groove  47 A at a prescribed position to which the ball  44  is engaged. In fitting the upper rubber plug holder  36  into the upper fixed block  40 , it is only required, as shown in FIG. 9B, to fit the operatively pushed part  48  and the fixed arm  47  into the slot  40 A to engage the ball  44  with the V-shaped groove  47 A formed in the fixed arm  47 . At that time, the operatively pushed part  48  is protruded from the side opposite to the insertion side of the slot  40 A. Accordingly, pushing the head of the operatively pushed part  48  easily detaches the upper rubber plug holder  36 . 
     As shown in FIG. 7, the upper insertion guide  38  has an insertion guide block  50  at which provided in a protruding manner is an insertion protrusion  49  in a sectionally arc shape, having a groove  49 A on its bottom surface for securing a wire insertion path when inserted in the tubular hole of the rubber plug  14 , a fixed arm  51  integrally formed at a side of the insertion guide block  50  and an operatively pushed part  52  integrally formed at an end of the fixed arm  51 . The fixed arm  51  has a V-shaped groove  51 A at a prescribed position like the upper rubber plug holder  36 . In fitting the upper insertion guide  38  into the slot  41 A of the upper movable block  41 , a ball not shown is engaged with the V-shaped groove  51 A. The operatively pushed part  52  is protruded from the side opposite to the insertion side of the slot  41 A. In the case of changing the upper insertion guide  38 , pushing the operatively pushed part  52  easily detaches the guide  38 . The upper holder supporting block  34  is configured to allow the movement of the operatively pushed part  52  and to make the operatively pushed part  52  exposed to be pushed easily. 
     The lower holder supporting block  35  has the same structure as that of the upper holder supporting block  34 . That is, the lower holder supporting block  35  has, as shown in FIG. 7, a lower fixed block  53  to which the lower rubber plug holder  37  is attached and a lower movable block  54  positioned closer to the rotary transporter  18  than the lower fixed block  53 . 
     The lower fixed block  53  has a slot  53 A penetrating along the apparatus-width direction. The lower movable block  54  also has a slot  54 A penetrating in the same direction. The lower movable block  54  is arranged to reciprocatingly movable by sliding on guide rods  55 ,  55  laid across the opposed surfaces of the lower fixed block  53  and the lower holder supporting block  35 . The lower movable block  54  is configured to be driven to reciprocatingly move along the guide rods  55 ,  55  by a drive means not shown in a prescribed timing. 
     As shown in FIG. 9A, the slot  53 A has an internal wall in which provided is a ball biased by a coil spring  56  to be protruded but not pushed out into the slot  53 A, which arrangement constitutes a ball plunger. Such a ball plunger is, not shown in the figure, is also provided in a slot  54 A of the lower movable block  54 . 
     The lower rubber plug holder  37  to be fitted into the slot  53 A of the lower fixed block  53  consists of a rubber plug holding block  59  having a rubber plug accommodating recess  58  at its top surface for accommodating the lower half of the rubber plug  14 , a fixed arm  60  integrally formed at a side of the rubber plug holding block  59  and an operatively pushed part  61  integrally formed at an end of the fixed arm  60 . The fixed arm  60  and the operatively pushed part  61  are integrally formed so as to extend generally in line with their total length set to be longer than the length of the slot  53 A. The fixed arm  60  has a V-shaped groove  60 A at a prescribed position to which the ball  57  is engaged. In fitting the lower rubber plug holder  37  into the lower fixed block  63 , it is only required, as shown in FIG. 9B, to fit the operatively pushed part  61  and the fixed arm  60  into the slot  53 A to engage the ball  57  with the V-shaped groove  60 A formed in the fixed arm  60 . At that time, the operatively pushed part  61  is protruded from the side opposite to the insertion side of the slot  53 A. Accordingly, pushing the head of the operatively pushed part  61  easily detaches the lower rubber plug holder  37 . 
     As shown in FIG. 7, the lower insertion guide  39  has a insertion guide block  63  at which provided in a protruding manner is an insertion protrusion  62  in a sectionally arc shape, having a groove  62 A on its top surface for securing a wire insertion path when inserted in the tubular hole of the rubber plug  14 , a fixed arm  64  integrally formed at a side of the insertion guide block  63  and an operatively pushed part  65  integrally formed at an end of the fixed arm  64 . The fixed arm  64  has a V-shaped groove  64 A at a prescribed position like the lower rubber plug holder  37 . In fitting the lower insertion guide  39  into the slot  54 A of the lower movable block  54 , a ball not shown is engaged with the V-shaped groove  64 A. The operatively pushed part  65  is protruded from the side opposite to the insertion side of the slot  54 A. In the case of changing the lower insertion guide  39 , pushing the operatively pushed part  65  easily detaches the guide  39 . The lower holder supporting block  35  is configured to allow the movement of the operatively pushed part  65  and to make the operatively pushed part  65  exposed to be pushed easily. 
     The upper holder supporting block  34  and the lower holder supporting block  35  are driven with a drive means not shown to be movable both in the direction of attaching/detaching to/from each other and in the longitudinal direction of the apparatus. The upper and lower movable blocks  41  and  54  are driven with a drive means not shown to move close to and apart from the upper and lower fixed blocks  40  and  53 . 
     At the rear of the rubber plug fitting section  13  (the opposite side to the rotary transporter  18 ), a wire end holder  66  is disposed as shown in FIGS. 3,  4  and  8 . The wire end holder  66  is supplied each time with a wire end  67  to be disposed thereon, over which end  67  the rubber plug  14  is fitted, as shown in the figures. 
     The rubber plug fitting apparatus  10  in this embodiment has been described in structure, and now will be described in function/operation. 
     The rotation and the vibration of the drum  15  in the rubber plug supply section  11  causes the rubber plugs  14  in the drum  15  aligned on the feeder  16  to be fed. The rubber plug  14  moved along the feeder to reach the rubber plug holder  22  in the rubber plug pusher  17  (See FIG. 6A) is pushed up by the escape pin  21  in a prescribed timing. At that time, the transporting pin  29  of the rotary transporter  18  awaits above the rubber plug holder  22 , so that the pushed-up movement of the rubber plug  14  causes the transporting pin  29  to be inserted in the tubular hole of the rubber plug  14 , which is thus held (in a state shown in FIGS.  5 A and  5 B). 
     After the rubber plug  14  is held with the transporting pin  29  facing downward, the driving shaft  31  of the drive pulley  32  is rotated to a prescribed rotational angle under a drive signal outputted from a controller not shown. The rotation is transmitted to the rotary block  28  which is then rotated 90 degrees through the endless belt  33  and the transmission pulley  30 . This rotational movement brings the transporting pin  29  holding the rubber plug  14  adjacent to the rubber plug fitting section  13 . 
     In this state, the upper and lower holder supporting blocks  34  and  35  spaced apart vertically are moved with a drive means not shown to a position where the upper and lower rubber plug holders  36  and  37  are placed above and below the rubber plug  14  held with the transporting pin  29 . Thereafter the upper and lower holder supporting blocks  34  and  35  are moved close to each other to enclose and hold the rubber plug  14  with the rubber plug accommodating recesses  45  and  58  of the upper and lower rubber plug holders  36  and  37 . With this state maintained, the upper and lower holder supporting blocks  34  and  35  are moved rearwardly (in the direction to pull the rubber plug  14  out of the transporting pin  29 ) with a drive means not shown, to separate the rubber plug  14  from the transporting pin  29 . Then the upper and lower movable blocks  41  and  54  are moved close to the upper and lower fixed blocks  40  and  53  with a drive means not shown. In this state, the upper and lower insertion guide  38  and  39  are joined and the insertion protrusions  49  and  62  constitute a pipe. With the movement of the upper and lower movable blocks  41  and  54 , the insertion protrusions  49  and  62  in a pipe is inserted into the tubular hole of the rubber plug  14  to secure a wire insertion space. 
     Then the rubber plug fitting section  13  holding the rubber plug  14  in this manner and the wire end holder  66  are brought closer to each other to insert the wire end  67  into the tubular hole of the rubber plug  14 . Thereafter, a known termination process can be performed. After the fitting of the rubber plug  14  over the wire end  67  in this manner, a new wire end  67  is set in the wire end holder  66  to repeat the above process, which provides efficient continuous fitting of the rubber plugs  14 . 
     In the rubber plug fitting apparatus  10  in this embodiment, the above structure makes it easy to attach/detach the upper and lower rubber plug holders  36  and  37  and the upper and lower insertion guides  38  and  39  to/from the upper and lower holder supporting blocks  34  and  35 . When the size or kind of the rubber plug  14  is changed, for example, this makes it easy to change the upper and lower rubber plug holders  36  and  37  and the upper and lower insertion guides  38  and  39  to the ones of size suitable for the new rubber plug  14  in a short time. Thus various kinds of rubber plugs can be fitted with the rubber plug fitting apparatus  10  without taking a lot of time for the change of the rubber plugs. Further, the upper and lower rubber plug holders  36  and  37  and the upper and lower insertion guides  38  and  39  can be attached/detached with a single push with the so-called ball plunger mechanism, which eliminates the need for special skill for the attachment/detachment, improving the workability. 
     The above embodiment is not intended to limit the scope of the invention. Various modifications are possible within the intended purpose of the structure. For example, although the rubber plug supply section  11  has the drum  15  and the feeder  16  in the above embodiment, another rubber plug supply means can be used. 
     Although the rubber plug  14  is transferred to the rubber plug fitting section  13  with the rotary transporter  18  in the above embodiment, another transfer means can be used. 
     The entire contents of Japanese Patent Application 2000-089898 (filed on Mar. 28, 2000) is incorporated herein by reference. 
     Although the invention has been described above by reference to certain embodiment of the invention, the invention is not limited to the embodiment described above. Modifications and variations of the embodiment described above will occur to those skilled in the art, in light of the above teachings. The scope of the invention is defined with reference to the following claims.