Abstract:
The present invention provides, in assembling an anti-vibration device having an inner cylinder, an outer cylinder, a rubber elastic member joining them and an intermediate cylinder fitted to the outer cylinder and internally forming a liquid chamber, an assembling apparatus for caulking an end of the outer cylinder while suppressing the occurrence of buckling without causing cracks, breakage or the like. This assembling device has a press-fit device to press-fit an internal unit joined with the inner cylinder and the intermediate cylinder through a rubber elastic member to the outer cylinder within a liquid tank, a caulking device to caulk an end of the outer cylinder of an assembly completed in press-fitting, and transporting means to transport the assembly from the press fit device to the caulking device. The caulking device can perform caulking in two stages of caulking.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to an apparatus for assembling an anti-vibrating device of a liquid-filled type principally used as a vehicular body mount or engine mount or the like. 
     2. Related Art 
     A liquid-filled-type anti-vibration device A, for example, as shown in FIG. 11 has been developed as a body mount to be interposed between a vehicular body and a frame such as a suspension on a support side to support the body in an anti-vibrating fashion. 
     This anti-vibration device A has an inner cylinder  1  made of a comparatively thick-walled metal to be coupled and fixed to one of the vehicular body and the frame on the suspension side and an outer cylinder  2  made of a metal to be coupled and fixed to the other. The inner and outer cylinders  1 ,  2  are joined through a rubber elastic member  3  vulcanization-bonded to an outer periphery of the inner cylinder  1  and an intermediate cylinder  4  fitted at an inner side of the outer cylinder. Furthermore, two liquid chambers  5   a ,  5   b  are provided between the inner and outer cylinder  1 ,  2  in locations opposed to each other sandwiching the inner cylinder  1 . These liquid chambers  5   a ,  5   b  are in mutual communication through an orifice passage  6 , thus obtaining a vibration damping effect due to an effect of liquid flow between the chambers. 
     The foregoing intermediate cylinder  4  is vulcanization-bonded to the outer periphery of the rubber elastic member  3 . The intermediate cylinder  4  has at one end an outwardly directed flange  4   a  and opened in a window form in the position corresponding to the chambers  5   a ,  5   b , and press-fitted to the inner side of the outer cylinder  3  through a sealing rubber layer  7  and fitted airtight, thereby forming the liquid chamber  5   a ,  5   b  between the cylinders  1 ,  2 . 
     Furthermore, the outer cylinder  2  has a flange  2   a  bent to an outer side with which the flange  4   a  of the intermediate cylinder  4  contacts. The flange  2   a  has an end  2   b  caulked inside and fixed in a manner wrapping from an outside an end edge of the flange  4   a  of the intermediate cylinder  4 , thereby firmly holding the fit state. 
     In the manufacture of the anti-vibration device A structured as above, previously prepared is an internal unit A 1  integrated with an inner cylinder  1  and an intermediate cylinder  4  through a rubber elastic member  3  by vulcanization-forming the rubber elastic member  3 . Separately from this, previously formed is an outer cylinder  2  having at one end a flange  2   a  and bent at the end  2   b  thereof to an axial direction as the chain line of FIG.  11 . 
     In an assembling process, in a liquid tank filled with a liquid such as ethylene glycol to be charged in the internal liquid chambers  5   a ,  5   b , the internal unit A 1  is press-fitted into the outer cylinder  2  in a direction from the flange  2   a  while discharging interior air, thereby bringing the flange  4   a  of the intermediate cylinder  4  into contact with the flange  2   a  of the outer cylinder  2 . Furthermore, in this state, the flange  2   a  of the outer cylinder  2  is caulked to be bent inward, thus completing the assembling. 
     In this assembling, conventionally the caulking at the flange end of the outer cylinder  2  has been made by a oncebending process. In this case, because the end  2   b  of the flange  2   a  of the outer cylinder  2  is bent inward by once caulking to an inward that is in generally a rectangular direction from the axial direction of the outer cylinder, the bend angle amounts to 90 degrees or greater and the deformation amount is large. There has been a possibility that the bend portion buckles readily causing cracking and breakage. Consequently, there has been a setback to reducing the product durability and quality and further yield of manufacture. 
     It is an object of the present invention to provide, as principally an assembling apparatus for a liquid-filled-type anti-vibration device, an assembling apparatus which can caulk an end edge of an outer cylinder while suppressing occurrence of buckling without causing crack or breakage, thereby improving the endurance and quality of an anti-vibration device to be assembled and further improving manufacture yield. 
     SUMMARY OF THE INVENTION 
     An apparatus for assembling an anti-vibration device of the present invention has an inner cylinder, an outer cylinder arranged outward of the inner cylinder, a rubber elastic member arranged between the inner and outer cylinders, an intermediate cylinder fitted inward of the outer cylinder, and a liquid chamber formed in an interior of the rubber elastic member, the anti-vibration device assembling apparatus comprising: a press-fit device for press-fitting an internal unit united with an inner cylinder and an intermediate cylinder through a rubber elastic member to an outer cylinder within a liquid tank; a caulking device for caulking an axial one end of the outer cylinder of an assembly completed of press-fitting; and transport means for transporting the assembly from the press-fit device to the caulking device; wherein the caulking device being provided to allow two stages of caulking by first and second two kinds of caulking dies including caulking to bend an end of the outer cylinder of the assembly by a predetermined angle less than 90 degrees and caulking to further bend the end of the outer cylinder already bent to a certain degree into a predetermined caulking form. 
     According to this assembling apparatus, an internal unit united with an internal cylinder and an intermediate cylinder through a rubber elastic member and an outer cylinder are supplied to the press-fit device to press-fit the internal unit to the outer cylinder within a liquid tank. An assembly thus completed in press-fitting is transported by proper transport means from the press-fit device to the caulking device to carry out caulking. On this occasion, a first-staged caulking is made by the first caulking die to bend an end of the outer cylinder of the assembly by a predetermined angle less than 90 degrees. Next, second-staged caulking is made by the second caulking die to bend furthermore the one end of the outer cylinder already bent to a certain degree and finally form it into a predetermined caulking form. 
     In this manner, when caulking one end of the outer cylinder, predetermined caulking is completed to a bend angle of about 90 degrees or greater by two-staged caulking with the first caulking die and second caulking die. 
     Due to this, as compared to the conventional case of once caulking to a predetermined angle, it is possible to prevent the occurrence of damage, such as cracks, and hence improve the endurance and quality of the anti-vibration device manufactured. Also, prevention is made against occurrence of cracks due to bending in caulking, the manufacture yield of the anti-vibration device is by far improved. 
     The caulking device may comprise a caulking lower die for supporting the assembly with the axial one end to be caulked positioned up, and first and second caulking dies vertically movably supported in the above of the lower die, the first caulking die for applying a first stage of caulking to the axial one end of said outer cylinder of said assembly supported in said lower die, and said second caulking die for applying a second stage of caulking to the one end in order for further bending into a predetermined form. 
     According to this caulking device, the assembly completed in press-fit in the press-fit device is supported in the caulking lower die with the axial end positioned up. In this state, the first caulking die is first descended relative to the lower die and first-staged caulking is made to bend the axial end of the outer cylinder of the assembly by a required predetermined angle less than 90 degrees. Next, the second caulking die is descended relative to the lower die and the one end of the outer cylinder somewhat bent as above is further bent into a predetermined form. This makes it possible to caulk the one end of the outer cylinder in two stages while holding it in the same support position, thereby suppressing the occurrence of buckling in the bend portion. 
     In the assembling apparatus of the invention, the first caulking die and second caulking die in the above of the lower die are movably provided in a transverse direction to an axis thereof and alternately oppositely positioned to the lower die. 
     Due to this, the first caulking die is previously positioned oppositely above the lower die. Due to the descend action of it, a first stage of caulking is made to the axial one end of the outer cylinder of the assembly supported in the lower die. Next, alternately to the first caulking die, the second caulking die is positioned oppositely above the lower die whereby the descend action of it can make a second stage of caulking. Accordingly, it is possible to automatically carry out caulking to a predetermined angle due to bending twice without the intervention of an operator, improving by far operationality. 
     In the assembling apparatus, the caulking lower die preferably has, in an axis portion, a support pin vertically movable to fit with and support the inner cylinder of the assembly, and first and second caulking dies have, in respective lower axis portions, pins to fit in an upper potion of an inner cylinder of the assembly due to descend action. Due to this, during caulking, the assembly completed in press-fit can be formed in the state that the inner cylinder is held at axial portion by the vertically fit pin and support pin. This can provide caulk-fixing evenly over the entire periphery without deviation. 
     Also, the transport means of the assembling apparatus may comprise an arm of a robot having, at a tip, clamp means to grip the internal unit and the assembly to carry out supply of the internal unit to the press-fit device, transport of the assembly completed of press-fitting from the press-fit device to the caulking device and taking the assembly completed of caulking out of the caulking device, in a manner related to press-fit and caulking action. This can automate and enhance the efficiency of a series of operations in assembling an anti-vibration device and caulking. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of an assembling apparatus for an anti-vibration device of the present invention; 
     FIG. 2 is a side view of the assembling apparatus; 
     FIG. 3 is a cross sectional plan view of the assembling apparatus; 
     FIG. 4 is a magnified front view of a press-fit device of the assembling apparatus in a state before press-fitting an internal unit to an outer cylinder; 
     FIG. 5 is a magnified front view of the press-fit device in a state of press-fit completion; 
     FIG. 6 is a magnified front view of the assembling apparatus omitting part of the caulking device; 
     FIG. 7 is a sectional view on line B—B of the caulking device; 
     FIG. 8 is a magnified sectional view of an essential part of the caulking device in a state that an assembly completed of press-fitting is held by a caulking lower die; 
     FIG. 9 is a magnified sectional view of an essential part in a state of caulking by a first caulking die; 
     FIG. 10 is a magnified sectional view of an essential part in a state of caulking by a second caulking die; and 
     FIG. 11 is a sectional view of an anti-vibration device. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Now a preferred embodiment of an anti-vibration-device assembling apparatus of the present invention will now be explained with reference to the drawings. 
     Herein, an anti-vibration device A to be assembled is similar to the anti-vibration device A exemplified in FIG. 11, and the outline of its structure and manufacture is as per the explanation in the background art and duplicated explanation will be omitted. Also, where reference in the below explanation is made to FIG. 11, the same reference numerals will be used. 
     FIG. 1 to FIG. 3 shows an overall structure of an assembling apparatus  10  according to an embodiment of the present invention. Explained is the outline of a structure of this assembling apparatus  10 . 
     In the assembling apparatus  10 , a table  12  is provided on a frame  11 . On the table  12 , a liquid tank  13  is provided that is filled with a liquid to be charged to the anti-vibration apparatus A being assembled. This apparatus  10  has a press-fit device  20  for press-fitting an internal unit A 1  integrated with the internal cylinder  1  and intermediate cylinder  4  of FIG. 11 through a rubber elastic member  3  into an outer cylinder  2  within the liquid tank  13 , and a caulking device  30  for caulking an axial one end of an outer cylinder  2  of an assembly A 2  completed in the press-fitting, particularly an end  2   b  of the flange  2   a , within the liquid tank  13 . Furthermore, on the backside of them (on the upper side in FIG.  3 ), a robot  40 , hereinafter described, is set up. 
     As the press-fit device  20 , a press-fit lower die  21  is provided on a bottom of the liquid tank  13  and a press-fit upper die  22  that is provided above the lower die  21  in a coaxial and vertically opposed relation. This press-fit upper die  22  is mounted at a lower end of urging means  24  having a drive source  23 , such as a hydraulic cylinder fixed at an upper portion of the frame  11 , and supported for vertical movement so that urging upon press-fit is made by descending of the same. 
     The press-fit lower die  21  is formed, as shown in FIG. 4, formed annular to receive the outer cylinder and in a corresponding form that an top peripheral edge of an bore can hold the flange  2   a  of the outer cylinder  2  in a fit state (chain line in FIG.  4 ). On an inner axis of the lower die  21 , a support pin  25  is vertically movably provided whose tip can fit with and support the inner cylinder  1  of the internal unit A 1  to be press-fit in the outer cylinder  2 . Also, the press-fit upper die  22  is vertically provided, at its lower peripheral edge, with an urging part  22   a  to press down the flange  4   a  of the intermediate cylinder  4  of the internal unit A 1 . Furthermore, on an inner axis of the urging part  22   a , a pin  26  projects to fit with the inner cylinder  1  of the internal unit A 1 . This pin  26  and the support pin  25  cooperatively hold and press-fit the internal unit A 1  in an aligning state to the outer cylinder  2 . 
     Meanwhile, as the caulking device  30 , a caulking lower die  33  is provided in a position other than that of the press-fit device  20  on the bottom of the liquid tank  13 , to support an assembly A 2  completed in press-fit in the press-fit device  20 . Also, in the above of the lower die  33  are provided first and second caulking dies  31 ,  32 . The first and second caulking dies  31 ,  32  are attached at a lower end of one of urging means  35  having a drive source  34 , such as a hydraulic cylinder, fixed in an upper portion of the frame  11  and supported for vertical movement. Particularly, the first and second caulking dies  31 ,  32  are attached slidable in a direction orthogonal to the axis between the axis of the lower die  33  and the position off the axis, and provided so that they alternately position oppositely above the axis with the lower die  33 . Due to this, provision is made to make predetermined caulking by descending action in a state corresponding position of the axis of the lower die  33 .  36  is advance/retract means for the hydraulic cylinder or the like to slide-move the both dies  31 ,  32 . 
     FIG. 1 shows first caulking die  31  opposed to caulking lower die  33 , while FIG. 7 shows second caulking die  32  opposed to caulking lower die  33 . 
     The caulking lower die  33  is formed annular to receive the outer cylinder  2  of an assembly A 2  having press-fit with outer cylinder hardware  3  in the internal unit  10  and in a corresponding form that an top peripheral edge of an bore can hold the flange  2   a  of the outer cylinder  2  in a fit state (chain line in FIG.  8 ), and further provided at outer portion with a recess to receive the first and second caulking dies  31 ,  32 . On the axis of the lower die  33 , a support pin  37  is provided for vertical movement whose tip can fit with the inner cylinder  1  of the assembly A 2  and support the same. 
     Meanwhile, the first and second caulking dies  31 ,  32  respectively have, in their lower end peripheries, annular projection  31   a ,  32   a  to urge the end  2   b  of the flange  2   a  of the outer cylinder  2  of the assembly A 2 . These projecting die portions.  31   a ,  32   a  are formed, in their tip peripheries, with curved surfaces  31   b ,  32   b  each to bend inward the flange end  2   b  by a predetermined angle of less than 90 degrees and subject it to predetermined caulking. 
     That is, the projecting die portion  31   a  of the first caulking die  31  is formed with the curved surface  31   b  to urge the flange end  2   b  of the outer cylinder  2  and bend it by a predetermined angle less than 90 degrees (e.g. 45 degrees) into a curbed form, as shown in FIG.  9 . Furthermore, the projecting die portion  32   a  of the second caulking die  32  is formed with a curved surface  32   b  to further bend, as shown in FIG. 10, the flange end  2   b  as bent by the first caulking die  31  and form it into a final predetermined caulking form, thus capable of making caulking in two stages. 
     Furthermore, on the axis at the inward of the first and second caulking dies  31 ,  32 , a pin  38  is projected downward to fit with the inner cylinder  1  of the assembly A 2  thereby enabling press-fit with the axis of the assembly A 2  held. 
     The robot  40  has an arm  41  movable up and down, left and right and back and forth through a plurality of joints. The arm  41  at its tip has a clamp  43  provided through a rotation mechanism  42 . This arm  41  is provided having a role as transporting means to grip the internal unit A 1  as a work being assembled in a predetermined supply section (not shown) to transport it to an air-discharging inversion section  15  and transport the internal unit A 1  after air discharge in the air-discharge inversion section  15  to the press-fit device  20  to supply it to a position above the outer cylinder  2  set in the press-fit lower die  21 , and a role as transporting means to grip the assembly A 2  completed in press-fit in the press-fit device  20  and transport it to the caulking lower die  33  of the press-fit device  30 . Furthermore, transport means is also provided to transport the assembly A 2  after completion of caulking to a liquid-cut inversion section  17  at an outside of the liquid tank  13 . These operations are set in relation to the operation of press-fit and caulking. 
     Incidentally, the air-discharge inversion section  15  is provided to rotate the internal unit A 1  transported by the arm  41  by a predetermined angle in opposite directions about a horizontal axis in FIG. 1 in the liquid within the liquid tank  13  and discharge the interior air due to vertical inversion of the unit. This inversion action may be made by holding by means other than a clamp  43  of the arm  41  or made in a held state by the clamp  43 . Also, the liquid-removal inversion section  17  is provided to support the assembly A 2  transported by the arm  41  outside the liquid tank  13  by supporting means  18  separate from the clamp  43  and discharge the external liquid due to rotation by a predetermined angle. 
     Hereunder, explanation will be made on a process of assembling an anti-vibration device  1  using the assembling apparatus  10  constructed as above. 
     The outer cylinder  2  is supplied and set in the press-fit lower die  21  within the liquid tank  13  of the press-fit device  20 , on which an internal unit A 1  is set as shown in FIG. 6 in a state of excluding the interior air. For example, in a state the support pin  25  at its tip is projected above from the liquid surface, the outer cylinder  2  is supplied and supported on the tip and supported as shown in FIG. 4 on the press-fit lower die  21  due to descending of the support pin  25 . Also, the internal unit A 1  is gripped by the clamp  43  at the tip of the arm  41  of the robot  40  and supplied from the air-discharge inversion section  15  to the above of the outer cylinder  2  where it is supported by fitting the inner cylinder  1  with the tip of the support pin  25 . If this done, the clamp  43  is removed and the press-fit upper die  22  is lowered by operating the urging means  24 . The pin  26  on the axis is fitted with in the inner cylinder  1  and the urging part  22   a  is caused to urge the flange  4   a  of the intermediate cylinder  4  of the internal unit A 1 , press-fitting the internal unit A 1  into the outer cylinder  2 . 
     When the press-fit is completed and the press-fit upper die  22  ascends, the clamp  43  of the robot  40  arm  41  gripping the assembly A 2  completed in press-fit ascends and transports it to the caulking device  30  in the liquid. By ascending the support pin  37  of the caulking device, the tip fits with and supports the inner cylinder  1  of the assembly A 2 . In this state, it is descended to fit the outer cylinder  2  of the assembly A 2  over the bore of the caulking lower die  33  and the flange  2   a  is supported on the upper peripheral edge of the lower die  33 , thus achieving setting as shown by the chain line of FIG.  8 . 
     At this time, the first caulking die  31  of the first and second caulking dies  31 ,  32  positions opposite above the lower die  33 . In this state, the first caulking die  31  descends due to the operation of the urging means  35 . By this descending, the pin  38  on the axis fits in the inner cylinder  1  and the projecting die  31   a  at its curved surface  31   b  urges the flange end  2   b  of the outer cylinder  2  to bend it inward by a required angle less than 90 degrees into a curved form, as shown in FIG.  9 . At this time, the support pin  37  and the pin  38  are fit in the inner cylinder  1  of the assembly A 2  and hold it at the axis, thus generally evenly bending the end  2   b  at its entire periphery without deviation. 
     Next, when the first caulking die  31  ascends, in place of the caulking die  31  the second caulking die  32  moves to the above of the caulking lower die  33  and positions opposite to the lower die  33 . In this state, by descending the second caulking die  32  due to the operation of the urging means  35  similarly to the above, the pin  38  fits in the inner cylinder  1  and supports it at the axis. Furthermore, the curved surface  32   b  of the projecting die portion  32   a  furthermore bends the flange end  2   b  of the outer cylinder  2  already somewhat bent by the first press-fir die  31  and forms it into a predetermined caulking state as shown in FIG.  10 . This caulks and fixes the end  2   b  of the flange  2   a  of the outer cylinder  2  over the flange  4   a  of the intermediate cylinder  4  in a state wrapping the end edge thereof. 
     Completing the caulking, a second caulking die  32  ascends. Thereafter, by ascending the support pin  37 , the assembly A 2  is pulled up from the caulking lower die  33 , and gripped by the clamp  43  of the robot arm  41  and transported to the liquid-removal inversion section  17 , being recovered after removal of liquid. 
     As described above, the flange end  2   b  at one end of the outer cylinder is caulked in divisional two stages by the first caulking die  31  and the second caulking dies  32 . Due to this, as compared with the case of once caulking it to a bend angle of 90 degrees or greater, it is possible to suppress the occurrence of buckling in the bend point and prevent the occurrence of damage such as cracks. Thus, the assembly product can be improved in quality. 
     Incidentally, the assembling processes by the assembling apparatus  10 , i.e. the supply of the internal unit A 1  and outer cylinder  2  to the press-fit device  20 , the press-fitting by the press-fit device  20 , the caulking by the caulking device  30 , transportation of the assembly A 2  and the like, are set for automatic operations as a series of operations. 
     The present invention is not limited to the above embodiment but to be construed including a wide scope of modifications within a range of not departing from the spirit of the invention.