Abstract:
An anti-vibration unit, which enables a reduction in man-hours to be achieved during manufacturing and a reduction in the number of parts, is provided. A boss member of an anti-vibration device is pressed into a press-fitting section of a second bracket so as to be firmly fixed. The omission of the bolt enables a corresponding reduction in the number of parts. Moreover, by omitting the bolt in this way, there is no need to form a female threaded section on the boss member of the anti-vibration device, thus enabling a corresponding reduction in man-hours during manufacturing. In addition, when chemically treating the boss member of the anti-vibration device, it is unnecessary to implement a step for protecting the female threaded section with a masking bolt, thus eliminating the need to attach and detach the masking bolt, which in turn enables a corresponding reduction in man-hours during manufacturing.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an anti-vibration unit, and relates specifically to an anti-vibration unit which enables reduction in the number of parts and reduction in man-hours to be achieved during manufacturing. 
       BACKGROUND ART 
       [0002]    Between a vehicle body of an automobile and an engine that is a vibration source, an anti-vibration device is arranged in order to suppress transmission of vibration to the vehicle body side. For example, in Patent Literature 1, an anti-vibration device (anti-vibration unit) of a so-called inverted type is disclosed in which, in an anti-vibration device body  18  (anti-vibration device) including a lower attaching tool  12  (boss member), an upper attaching tool  14  (outer tube member) of a tubular shape, and an anti-vibration base  16  formed of a rubber-like elastic body connecting both of these attaching tools  12 ,  14  to each other, the lower attaching tool  12  is attached to a vehicle body  1  side through a second bracket  22  of a frame shape in front view that surrounds the periphery thereof, and the upper attaching tool  14  is attached to an engine  2  side through a first bracket  20  that is extended toward the side. 
       CITATION LIST 
     Patent Literature 
       [0000]    
       
         Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2009-014080 (paragraph [0015], FIG. 1 to FIGS. 3 and the like) 
       
     
       SUMMARY OF INVENTION 
     Technical Problem 
       [0004]    However, according to the technology of Patent Literature 1 described above, the structure is such that a female threaded section  24  is recessively arranged in the lower surface of the lower attaching tool  12  and the lower attaching tool  12  is fixed to the second bracket  22  by screwing a bolt  80  that is inserted to a bolt insertion hole  78  of the second bracket  22  to the female threaded section  24  of the lower attaching tool  12 . Therefore the bolt  80  is required, which increases the number of parts. Also, the man-hours during manufacturing are increased because it is necessary to form the female threaded section  24  in the lower attaching tool  12 . Further, when chemically treating the lower attaching tool  12 , it is necessary to protect the female threaded section  24  with a masking bolt, and the attaching and detaching work of the masking bolt increases the man-hours during manufacturing. 
         [0005]    The present invention has been developed in order to address the problems described above, and its object is to provide an anti-vibration unit which enables reduction in the number of parts and reduction in man-hours to be achieved during manufacturing. 
       Solution to Problem and Advantageous Effects of Invention 
       [0006]    According to the anti-vibration unit described in claim  1 , a press-in section formed in a boss member of an anti-vibration device is pressed in to a press-fitting section formed in a fixing member of a second bracket, and the boss member of an anti-vibration device is thereby fixed (press-in-fixed) to the fixing member of the second bracket. Thus, compared to the situation in which the boss member of the anti-vibration device is fixed (fastened) to the fixing member of the second bracket with a bolt, the bolt is unnecessary, enabling corresponding reduction in the number of parts. Moreover, by omitting the bolt in this way, it is not necessary to form a female threaded section on the boss member of the anti-vibration device, enabling corresponding reduction in man-hours during manufacturing. In addition, when chemically treating the boss member of the anti-vibration device, it is not necessary to implement a step of protecting the female threaded section with a masking bolt, thus the work of attaching and detaching the masking bolt is unnecessary, which in turn enables corresponding reduction in man-hours during manufacturing. 
         [0007]    According to the anti-vibration unit described in claim  2 , in addition to the effect exerted by the anti-vibration unit described in claim  1 , the boss member of the anti-vibration device can be firmly fixed to the fixing member of the second bracket. It is because, in the press-in section of the boss member, an extension section is extended outward in the radial direction from a shaft section that projects from the lower surface side of the base section, whereas in the press-fitting section formed of the fixing member, an extension section press-fitting space and a shaft section press-fitting space are formed as spaces having a cross-sectional shape corresponding to the external shape of the extension section of the press-in section of the boss member and the shaft section, and the press-in section of the boss member is pressed in to the press-fitting section of the fixing member through an opening in the side surface of the fixing member along the direction orthogonal to the axis of the anti-vibration device. 
         [0008]    That is, according to claim  2 , when the first bracket is relatively displaced with respect to the second bracket in the axial direction of the anti-vibration device, the extension section in the press-in section of the boss member engages with the inner wall surface of the space in the press-fitting section of the fixing member, and thereby a state the boss member of the anti-vibration device is fixed to the fixing member of the second bracket can be maintained. The same is true when relative displacement to the prying direction (the direction of inclining the axis of the anti-vibration device) is combined thereto. 
         [0009]    On the other hand, according to claim  2 , even when the first bracket is relatively displaced with respect to the second bracket in the direction orthogonal to the axis of the anti-vibration device and the direction parallel to the press-in direction (that is, even when the outer tube member is displaced by the first bracket on a parallel with the opposite direction of the press-in direction of the boss member), a force in the direction of inclining the extension section is also generated in the boss member by elastic deformation of an anti-vibration base, because the anti-vibration base is interposed between the outer tube member and the boss member, and thereby the extension section in the press-in section of the boss member engages with the inner wall surface of the space in the press-fitting section of the fixing member. Thus, the press-in section of the boss member can be prevented from slipping off from the press-fitting section of the fixing member. As a result, a state the boss member of the anti-vibration device is fixed to the fixing member of the second bracket can be maintained. 
         [0010]    According to the anti-vibration unit described in claim  3 , in addition to the effect exerted by the anti-vibration unit described in claim  2 , the press-fitting section of the fixing member includes a positioning wall formed at the final end that is on the opposite side of the opening in the side surface of the fixing member. Thus, pressing-in can be restricted by abutment of the press-in section of the boss member upon the positioning wall when the press-in section of the boss member is pressed in through the opening in the side surface of the fixing member. That is, the press-in position can be positioned by pressing in the press-in section of the boss member until abutting upon the positioning wall, therefore the press-in process can be simplified, the control cost thereof can be reduced, the press-in position is prevented from being dispersed, and the positional accuracy of the press-in position can be improved. 
         [0011]    Also, in the product state, a state the press-in section of the boss member abuts upon the positioning wall in the press-fitting section of the fixing member is achieved. Therefore, when the first bracket is relatively displaced with respect to the second bracket, the input load can be counteracted utilizing engagement of the press-in section and the positioning wall with each other. Thus, a state the boss member is fixed to the fixing member can be securely maintained. 
         [0012]    Also, “the distal end that is on the opposite side of the opening in the side surface of the fixing member” means the distal end in the press-in direction in pressing in the boss member (that is the position where the boss member is in finally pressed). It is not required that the positioning wall is positioned at the end in the width direction (the press-in direction) of the fixing member. 
         [0013]    According to the anti-vibration unit described in claim  4 , in addition to the effect exerted by the anti-vibration unit described in claim  3 , the engagement area of the press-fitting section with the inner wall surface in the extension section press-fitting space can be enlarged because the extension section of the boss member is formed into a disk shape. Thus, utilizing engagement of the extension section with the inner wall surface of the extension section press-fitting space, a state the boss member is fixed to the fixing member of the second bracket can be more securely maintained. 
         [0014]    Also, in the product state, the input load can be counteracted utilizing engagement of the extension section and the positioning wall with each other because the positioning wall is formed so as to curve in an arc shape corresponding to the disk shape of the extension section. Thus, a state the boss member is fixed to the fixing member can be securely maintained. 
         [0015]    In this case, the width dimension of the press-fitting section is prevented from increasing while enabling positioning of the press-in position of the boss member, and the second bracket can be miniaturized because the positioning wall is formed so as to curve in an arc shape. Also, when the extension section of the boss member is formed into a square plate shape for example, it is necessary to reduce the plate thickness of the entire positioning wall in order to suppress the width dimension (the dimension in the press-in direction) of the press-fitting section. In claim  4 , however, the plate thickness in both ends of the positioning wall can be made thick and stiffness of the positioning wall can be secured because the positioning wall is formed so as to curve in an arc shape. 
         [0016]    According to the anti-vibration unit described in claim  5 , in addition to the effect exerted by the anti-vibration unit described in claim  4 , the positioning wall includes an opening formed so as to open in the center part in the width direction, allowing the scraping chips can be discharged to the outside through the opening when scraping chips are formed in pressing in the boss member to the press-fitting section. Thus, the scraping chips are not caught, the extension section of the boss member can be tightly attached to the positioning wall, and therefore the positional accuracy of the press-in position of the boss member can be secured. 
         [0017]    Here, the plate thickness in the center part in the width direction becomes thin because the positioning wall is formed so as to curve in an arc shape. In this case, unless the opening is arranged, it is necessary to increase the plate thickness of the positioning wall (the center part in the width direction) in order to secure the strength (to prevent breakage) of the center part in the width direction when the press-in position of the boss member is restricted, and the size of the second bracket (the fixing member) is increased correspondingly. On the other hand, in claim  5 , the second bracket (the fixing member) can be miniaturized while securing the strength of the positioning wall (while preventing the breakage of the center part in the width direction) because the opening is formed in the center in the width direction of the positioning wall. 
         [0018]    According to the anti-vibration unit described in claim  6 , in addition to the effect exerted by the anti-vibration unit described in claim  4  or  5 , it is not necessary to consider the orientation in the peripheral direction because the boss member is formed into an axially symmetric shape and is disposed so as to be coaxial with the axis of the anti-vibration device. Thus, when the boss member is to be arranged inside the vulcanizing mold in vulcanizing molding of the anti-vibration base, the work can be executed without considering the orientation around the axis of the boss member in arranging the boss member. Similarly, when the outer tube member of the anti-vibration device is to be pressed in to the first bracket and is to be held, the work can be executed without considering the orientation around the axis of the anti-vibration device in pressing in the outer tube member. That is, the work of positioning the boss member or the anti-vibration device in the peripheral direction can be omitted, and the man-hours during manufacturing can be reduced correspondingly. 
         [0019]    According to the anti-vibration unit described in claim  7 , in addition to the effect exerted by the anti-vibration unit described in any of claims  3  to  6 , the positioning wall is recessively arranged in the surface on the side upon which the press-in section of the boss member abuts and includes a groove section extended in a groove shape along at least a part of the outer periphery that continues to the inner wall surface side of the press-fitting section. Therefore the scraping chips can be stored in the groove section when scraping chips are generated at the time the press-in section of the boss member is pressed in to the press-fitting section of the fixing member. That is, when the scraping chips are caught between the press-in section of the boss member and the positioning wall, the press-in position of the press-in section of the boss member is dispersed, while, according to claim  7 , the positional accuracy of the press-in position of the boss member can be secured because the scraping chips can be stored in the groove section and the press-in section of the boss member can be tightly attached to the positioning wall. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0020]      FIG. 1  ( a ) is a top view of an anti-vibration unit in a first embodiment of the present invention, and (b) is a front view of the anti-vibration unit as viewed in the direction of an arrow Ib of  FIG. 1(   a ). 
           [0021]      FIG. 2  is a cross-sectional side view of the anti-vibration device. 
           [0022]      FIG. 3  ( a ) is a partially enlarged front view of the anti-vibration device, and (b) is a cross-sectional view of the boss member taken from the line IIIb-IIIb of  FIG. 3(   a ). 
           [0023]      FIG. 4  is a top view of the first bracket. 
           [0024]      FIG. 5  ( a ) is a front view of the second bracket, and (b) is a cross-sectional view of the second bracket  30  taken from the line Vb-Vb of  FIG. 5  ( a ). 
           [0025]      FIG. 6  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit before pressing-in, and (b) and (c) are a partially enlarged cross-sectional view and a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0026]      FIG. 7  ( a ) is a partially enlarged front view of a second bracket in the second embodiment, (b) is a partially enlarged cross-sectional view of the second bracket taken from the line VIIb-VIIb of  FIG. 7(   a ), and ( c ) is a partially enlarged top view of the second bracket as viewed from the direction of the arrow VIIc of  FIG. 7(   a ). 
           [0027]      FIG. 8  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit before pressing-in, (b) and (c) are a partially enlarged cross-sectional view and a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0028]      FIG. 9  ( a ) is a partially enlarged cross-sectional view of a second bracket in the third embodiment, and (b) is a partially enlarged rear view of the second bracket as viewed from the direction of the arrow IXb of  FIG. 9(   a ). 
           [0029]      FIG. 10  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0030]      FIG. 11  ( a ) is a partially enlarged cross-sectional view of an anti-vibration unit after pressing-in in the fourth embodiment, and (b) is a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0031]      FIG. 12  ( a ) is a partially enlarged front view of an anti-vibration device in the fifth embodiment, and (b) is a cross-sectional view of a boss member taken from the line XIIb-XIIb of  FIG. 12(   a ). 
           [0032]      FIG. 13  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0033]      FIG. 14  ( a ) is a partially enlarged front view of a second bracket in the sixth embodiment, (b) is a partially enlarged cross-sectional view of the second bracket taken from the line XIVb-XIVb in  FIG. 14(   a ), and ( c ) is a partially enlarged cross-sectional view of the second bracket taken from the line XIVc-XIVc in  FIG. 14(   b ) 
           [0034]      FIG. 15  ( a ) is a partially enlarged front view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged cross-sectional view of the anti-vibration unit taken from the line XVb-XVb of  FIG. 15(   a ). 
           [0035]      FIG. 16  ( a ) is a partially enlarged front view of an anti-vibration device in the seventh embodiment, and (b) is a cross-sectional view of a boss member taken from the line XVIb-XVIb of  FIG. 16(   a ). 
           [0036]      FIG. 17  ( a ) is a partially enlarged front view of the second bracket, and (b) is a partially enlarged top view of the second bracket as viewed from the arrow XVIIb of  FIG. 17(   a ). 
           [0037]      FIG. 18  ( a ) is a partially enlarged front view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged cross-sectional view of the anti-vibration unit taken from the line XVIIIb-XVIIIb of  FIG. 18(   a ). 
           [0038]      FIG. 19  is a cross-sectional view of the anti-vibration unit before pressing-in in the eighth embodiment. 
           [0039]      FIG. 20  ( a ) is a partially enlarged front view of the anti-vibration device in the modification, and (b) is a bottom view of the boss member as viewed in the direction of the arrow XXb of  FIG. 20(   a ). 
           [0040]      FIG. 21  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged front view of the anti-vibration unit  501  after pressing-in. 
           [0041]      FIG. 22  ( a ) is a partially enlarged cross-sectional view of the second bracket in the modification, and (b) is a partially enlarged rear view of the second bracket as viewed from the direction of the arrow XXIIb of  FIG. 22(   a ). 
           [0042]      FIG. 23  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0043]      FIG. 24  ( a ) is a partially enlarged cross-sectional view of the second bracket in the modification, and (b) is a partially enlarged rear view of the second bracket as viewed from the direction of the arrow XXIVb of  FIG. 24(   a ). 
           [0044]      FIG. 25  ( a ) is a partially enlarged cross-sectional view of the anti-vibration unit after pressing-in, and (b) is a partially enlarged front view of the anti-vibration unit after pressing-in. 
           [0045]      FIG. 26   FIG. 26  is cross-sectional view showing the process of pressing-in of the anti-vibration unit in the modification, (a) corresponds to a state before pressing-in, (b) corresponds to a state in the middle of pressing-in, and (c) corresponds to a state after pressing-in respectively. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0046]    Hereinafter, preferred embodiments of the present invention will be described referring to the attached drawings.  FIG. 1(   a ) is a top view of an anti-vibration unit  1  in a first embodiment of the present invention, and  FIG. 1(   b ) is a front view of the anti-vibration unit  1  as viewed in the direction of an arrow Ib of  FIG. 1(   a ). 
         [0047]    The anti-vibration unit  1  is a device for not transmitting vibration of an engine of an automobile to a vehicle body (not illustrated) while supporting and fixing the engine (not illustrated). The anti-vibration unit  1  includes an anti-vibration device  10  in which a boss member  11  and an outer tube member  12  are connected with each other by an anti-vibration base  13  formed of a rubber-like elastic body (refer to  FIG. 3  with respect to all of them), a first bracket  20  holding the outer tube member  13  of the anti-vibration device  10  and attached to the engine side, and a second bracket  30  fixed with the boss member  11  of the anti-vibration device  10  and attached to the vehicle body side. 
         [0048]    The anti-vibration device  10  is disposed in a vertical attitude in which the axial direction agrees to the vertical direction and is disposed in an inverted state with the boss member  11  side coming to the downward side, and the periphery thereof is surrounded by the second bracket  30 . The first bracket  20  is extended horizontally toward the outside in the radial direction (the direction orthogonal to the axis; upward in  FIG. 1(   a )) from the side of the anti-vibration device  10 . 
         [0049]    Also, in the first bracket  20  and the second bracket  30 , attaching holes h 1 , h 2  are bored at three positions respectively, and the first bracket  20  and the second bracket  30  are fastened and fixed to the engine side and the vehicle body side by bolts that are inserted to these respective attaching holes h 1 , h 2 . Further, a stopper rubber SG is furnished on the anti-vibration device  10  and the first bracket  20 , and the upper surface side of the anti-vibration device  10  and the outer periphery side of a body section  21  (refer to  FIG. 4 ) of the first bracket  20  are covered by the stopper rubber SG. 
         [0050]    Also, in a state where the anti-vibration unit  1  supports and fixes the engine of the automobile to the vehicle body (so-called 1 W state), the anti-vibration base  13  is compressed and deformed by the weight of the engine, and a predetermined gap is formed correspondingly between the upper end side of the anti-vibration device  10  and a connection member  33  of the second bracket  30 . 
         [0051]    Next, referring to  FIG. 2  to  FIG. 5 , the anti-vibration device  10 , the first bracket  20  and the second bracket  30  forming the anti-vibration unit  1  will be described respectively. 
         [0052]      FIG. 2  is a cross-sectional side view of the anti-vibration device  10 , and corresponds to the vertical cross section when cut by a plane including the axis O. Also, in  FIG. 2 , a state where the anti-vibration device  10  is held by the first bracket  20  is illustrated. The cross section of the first bracket  20  in this  FIG. 2  corresponds to the cross section taken from a line II-II of  FIG. 4 . 
         [0053]    As shown in  FIG. 2 , the anti-vibration device  10  mainly includes the boss member  11  attached to the vehicle body side through the second bracket  30  (refer to  FIG. 1 ), the outer tube member  12  of a tubular shape attached to the engine side through the first bracket  20 , and the anti-vibration base  13  connecting both of these members  11 ,  12  to each other and formed of a rubber-like elastic body. 
         [0054]    The boss member  11  includes a base section  11   a  formed into a generally truncated cone shape cross section narrowing upward, a shaft section  11   b  projecting downward (the lower side in  FIG. 2 ) from the base section  11   a , and an extension section  11   c  (refer to  FIG. 3 ) extending outward in the radial direction from the projection distal end of the shaft section  11   b , and is integrally formed of an aluminum alloy. The base section  11   a  and the shaft section  11   b  are formed so as to be symmetric around the axis O. Also, the detailed configuration of the boss member  11  will be described below referring to  FIG. 3 . 
         [0055]    The outer tube member  12  is formed of an iron and steel material into a tubular shape with the upper and lower ends (the upper side and the lower side in  FIG. 2 ) being opened, and is disposed above (the upper side in  FIG. 2 ) the boss member  11  in a coaxial manner. Also, the outer tube member  12  is configured to have a step with a tubular part of a large diameter disposed on the lower side (the lower side in  FIG. 2 ) of the step and a tubular part of a small diameter disposed on the upper side (the upper side in  FIG. 2 ) of the step respectively, and the tubular part of a large diameter is pressed and held in the axial direction to the first bracket  20 . 
         [0056]    The anti-vibration base  13  is formed of a rubber-like elastic body into a generally truncated cone shape cross section narrowing downward symmetric around the axis O, and is vulcanizingly adhered between the outer surface in the base section  11   a  of the boss member  11  and the inner wall surface of the outer tube member  12 . 
         [0057]    Inside the outer tube member  12 , a diaphragm  14 , a partition member  15 , and an elastic partition membrane  16  are disposed. The diaphragm  14  is formed from a rubber-like elastic body into a rubber membrane shape having a partial sphere shape, and is furnished on the upper end side (the upper side in  FIG. 2 ) of the outer tube member  12  in a tightly attached (watertight) state. As a result, a liquid enclosure chamber where liquid is enclosed is formed between the lower surface side of the diaphragm  14  and the upper surface side of the anti-vibration base  13 . 
         [0058]    In the liquid enclosure chamber, an antifreeze liquid (not illustrated) such as ethylene glycol and the like is enclosed. The partition member  15  is a member that partitions the liquid enclosure chamber into a first liquid chamber on the anti-vibration base  13  side and a second liquid chamber on the diaphragm side, and, on the outer periphery side thereof, an orifice flow passage that makes the first liquid chamber and the second liquid chamber communicate with each other is formed. Also, in the center of the partition member  15 , a pair of opposing walls where plural openings are formed respectively is arranged so as to oppose each other, and the elastic partition membrane  16  formed of a rubber-like elastic body into a disk shape is stored between the opposing walls. 
         [0059]    Further, by invertingly arranging the anti-vibration device  10 , attaching the boss member  11  on the vehicle body side, and attaching the outer tube member  12  on the engine side as the present embodiment, a part of the vibration transmission route from the partition member  15  to the vehicle body side can be formed by the anti-vibration base  13 . Thus, when the elastic partition membrane  16  collides on the opposition walls of the partition member  15  and the restriction plate vibrates, the vibration can be surely prevented from being transmitted to the vehicle body side by the vibration insulation effect of the anti-vibration base  13  that constitutes a part of the vibration transmission route, and generation of noise can be reduced. 
         [0060]    Next, detailed configuration of the boss member  11  will be described referring to  FIG. 3 .  FIG. 3(   a ) is a partially enlarged front view of the anti-vibration device  10 , and  FIG. 3(   b ) is a cross-sectional view of the boss member  11  taken from the line IIIb-IIIb of  FIG. 3(   a ).  FIG. 3(   a ) corresponds to the front view of the anti-vibration device  10  as viewed along the direction of the arrow IIIa of  FIG. 2 . 
         [0061]    As shown in  FIG. 3 , with respect to the boss member  11 , the shaft section  11   b  projects downward from the base section  11   a , the extension section  11   c  is formed so as to extend from the projection distal end of the shaft section  11   b  outward in the radial direction (the direction orthogonal to the axis O), and a part of the shaft section  11   b  and the extension section  11   c  are made to be the press-in section that is pressed in to the press-fitting section  35  of the second bracket  30 . 
         [0062]    The shaft section  11   b  is formed as a shaft-like body with a circular cross section symmetric around the axis O, and, with respect to the extension section  11   c , a pair of flat plate shapes whose thickness dimension (the dimension in the vertical direction in  FIG. 3(   a )) is constant and whose width dimension (the dimension in the vertical direction in  FIG. 3(   b )) is equal to the diameter of the shaft section  11   b  is extended toward the directions opposite to each other with respect to the shaft section  11   b  in between. Thus, in the front view shown in  FIG. 3(   a ), the press-in section (the shaft section  11   b  and the extension section  11   c ) of the boss member  11  becomes a generally T-shape. 
         [0063]    A rubber membrane  13   a  covering the outer wall surface of the boss member  11  continues to the anti-vibration base  13 . This rubber membrane  13   a  covers only the outer wall surface (the outer peripheral surface and the lower surface) of the base section  11   a , and does not cover the outer wall surface of the shaft section  11   b  and the outer wall surface of the extension section  11   c . That is, the shaft section  11   b  and the extension section  11   c  are formed so that the outer wall surfaces thereof are exposed. 
         [0064]    Next, the first bracket  20  will be described referring to  FIG. 4 .  FIG. 4  is a top view of the first bracket  20 . The perpendicular direction of the paper surface of  FIG. 4  corresponds to the press-in direction of the anti-vibration device  10  (that is, the axis O direction after pressing-in; refer to  FIG. 2 ). 
         [0065]    As shown in  FIG. 4 , the first bracket  20  mainly includes the body section  21  of a flat plate shape, and a block-like extended section  22  that is extended diagonally from the corner on one side (the right side in  FIG. 4 ) of the body section  21 . At the corner on the other side (the left side in  FIG. 4 ) of the body section  21  and both sides of the extended section  22 , the attaching holes h 1  described above are bored respectively. By screwing the bolts that are inserted to the attaching holes h 1  to the engine side, the first bracket  20  is fastened and fixed to the engine side with the lower surface side (the back side in  FIG. 4 ) as the attaching surface. 
         [0066]    Below the body section  21 , a press-in hole  21   a  of a circular shape in the top view is bored. To this press-in hole  21   a , the outer tube member  12  of the anti-vibration device  10  is pressed in the axis O direction, and thereby the anti-vibration device  10  (the outer tube member  12 ) is held by the first bracket  20  (refer to  FIG. 1  and  FIG. 2 ). Also, on both side surfaces (the right side and the left side in  FIG. 4 ) of the body section  21 , stopper surfaces  21   b  formed as flat surfaces are formed. At the time of inputting large displacement, the stopper orthogonal effect is exerted by abutment of the stopper surfaces  21   b  upon erection members  32  of the second bracket  30  through the stopper rubber SG (refer to  FIG. 1 ) that is furnished on the anti-vibration device  10 . 
         [0067]    Next, the second bracket  30  will be described referring to  FIG. 5 .  FIG. 5(   a ) is a front view of the second bracket  30 , and  FIG. 5(   b ) is a cross-sectional view of the second bracket  30  taken from the line Vb-Vb of  FIG. 5(   a ). Also, in  FIG. 5(   a ), a part of a fixing member  31  and the erection member  32  is illustrated in a partial cross-sectional view. 
         [0068]    The second bracket  30  is a member interposed between the anti-vibration device  10  and the vehicle body side. The second bracket  30  includes the fixing member  31  to which the boss member  11  (refer to  FIG. 3 ) of the anti-vibration device  10  is fixed, the pair of erection members  32  erected upward from both sides (the left side and the right side in  FIG. 5(   a )) of the fixing member  31  and disposed so as to oppose each other with the anti-vibration device  10  in between, and the connection member  33  connecting erection distal ends of the pair of erection members  32  each other and disposed so as to oppose the fixing member  31  with the anti-vibration device  10  in between. These respective members  31  to  33  are integrally formed of an aluminum alloy into a frame shape in a front view. 
         [0069]    Also, the opposing surfaces (the inner wall surfaces) of the erection members  32  are formed as flat surfaces disposed in parallel so as to oppose each other at a predetermined interval, the lower surface (the inner wall surface) of the connection member  33  is formed as a flat surface that is vertical to the inner wall surfaces of the erection members  32  (that is, vertical to the axis of the anti-vibration device  10 ), and these inner wall surfaces function as stopper surfaces that receive the anti-vibration device  10  or the first bracket  20  at the time large displacement is inputted and restrict the displacement. 
         [0070]    The fixing member  31  includes fastened sections  34  and a press-fitting section  35 , and these both sections  34 ,  35  are formed integrally. The fastened sections  34  are portions attached on the vehicle body side, and are formed on both ends (the left side and the right side in  FIG. 5(   a )) of the fixing member  31 . The fastened sections  34  are formed into a plate shape, bored with the attaching holes h 2  described above in the plate thickness direction (the vertical direction in  FIG. 5(   a )), and fastened and fixed to the vehicle body side with the lower surface side (the lower side in  FIG. 5(   a )) as the attaching surface by screwing the bolts that are inserted to the attaching holes h 2  to the vehicle body side. 
         [0071]    The press-fitting section  35  is positioned between both of the fastened sections  34 , is a portion to which the boss member  11  (refer to  FIG. 3 ) of the anti-vibration device  10  is pressed in, and includes an extension section press-fitting space  36  and a shaft section press-fitting space  37 . The extension section press-fitting space  36  is a space where the extension section  11   c  (refer to  FIG. 3 ) in the boss member  11  of the anti-vibration device  10  is pressed in, is formed into a cross-sectional shape corresponding to the external shape of the extension section  11   c  pressed in, and includes openings in the side surfaces on both sides (the front side and the back side of the paper surface in  FIG. 5(   a )) of the press-fitting section  35 . 
         [0072]    That is, with respect to the extension section press-fitting space  36 , the shape in the front view shown in  FIG. 5(   a ) (that is, as viewed in the press-in direction described below) is made into a shape similar to the shape in the front view (as viewed in the press-in direction) of the extension section  11   c  in the boss member  11  of the anti-vibration device  10  (refer to  FIG. 3(   a )), and the shape in the front view of the extension section press-fitting space  36  is made smaller than the shape in the front view in the extension section  11   c . Thus, the allowance for pressing-in at the time of pressing-in is secured. 
         [0073]    The shaft section press-fitting space  37  is formed as a space with a cross-sectional shape through which at least the shaft section  11   b  (refer to  FIG. 3 ) in the boss member  11  of the anti-vibration device  10  can pass, with the lower surface side of the space to communicate with the upper surface side of the extension section press-fitting space  36 , and includes openings in the side surfaces on both sides (the front side and the back side of the paper surface in  FIG. 5(   a )) and the upper surface (the surface on the upper side in  FIG. 5(   a ); the surface opposing the connection member  33 ) of the press-fitting section  35 . 
         [0074]    That is, with respect to the shaft section press-fitting space  37 , the width dimension (the dimension in the right/left direction in  FIG. 5(   a )) in the front view (that is, as viewed in the press-in direction described below) shape shown in  FIG. 5(   a ) is made generally equal to the diameter dimension of the shaft section  11   b  of the boss member  11 , and is smaller than the width dimension (the dimension in the right/left direction in  FIG. 5(   a )) of the extension section press-fitting space  36 . Thus, above the extension section press-fitting space  36  (the upper side in  FIG. 5(   a )), a plate-like restriction wall  38  that extends with the shaft section press-fitting space  37  in between is formed. 
         [0075]    Also, the width dimension of the shape in the front view of the shaft section press-fitting space  37  may be larger than the diameter dimension of the shaft section  11   b  of the boss member  11  as far as it is smaller than the width dimension (the dimension in the right/left direction in  FIG. 5(   a )) of the extension section press-fitting space  36  (that is, as far as the restriction wall  38  can be formed). Alternatively the width dimension may be smaller than the diameter dimension of the shaft section  11   b  of the boss member  11  as far as the shaft section  11   b  can pass through in the press-in direction. Further, in the present embodiment, the shape in the front view (the cross-sectional shape when cut by an imaginary plane vertical to the press-in direction (the direction vertical to the paper surface in  FIG. 5(   a ))) of the extension section press-fitting space  36  and the shaft section press-fitting space  37  is made into an equal cross-sectional shape along the press-in direction. 
         [0076]    A manufacturing method of the anti-vibration unit that is configured as described above will be described referring to  FIG. 6 .  FIG. 6(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  1  before pressing-in, and  FIG. 6(   b ) and  FIG. 6(   c ) are a partially enlarged cross-sectional view and a partially enlarged front view of the anti-vibration unit  1  after pressing-in. The cross section of the anti-vibration device  10  of  FIG. 6(   a ) and  FIG. 6(   b ) corresponds to the cross section of  FIG. 2 , and the cross section of the second bracket  30  of  FIG. 6(   a ) and  FIG. 6(   b ) corresponds to the cross section of FIG.  5 ( b ). 
         [0077]    In manufacturing the anti-vibration unit  1 , the outer tube member  12  of the anti-vibration device  10  is pressed in to the press-in hole of the first bracket  20  in the axis O direction, and the outer tube member  12  of the anti-vibration device  10  is held by the first bracket  20  (the first bracket holding step; refer to  FIG. 2 ). Next, after the stopper rubber SG is furnished from the upper end side (the upper side in  FIG. 2 ) of the anti-vibration device  10 , the boss member  11  (the press-in section) of the anti-vibration device  10  is pressed in to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30 , and the boss member  11  of the anti-vibration device  10  is fixed to the second bracket  30  (the second bracket fixing step; refer to  FIG. 1(   b )). Thus, manufacturing of the anti-vibration unit  1  is completed. 
         [0078]    In assembling the anti-vibration device  10 , first, the rubber-like elastic body is filled inside the vulcanizing mold where the boss member  11  and the outer tube member  12  have been arranged, and a molded body obtained by connecting the boss member  11  and the outer tube member  12  by the anti-vibration base  13  is vulcanizingly molded. Next, the partition member  15  and the diaphragm  14  are fitted to the molded body successively through the opening of the outer tube member  12 , and the entire periphery section of the opening (the upper end of the tubular section of the small diameter) of the outer tube member  12  is subjected to diameter reduction work (drawing work) in the radial direction. Thus, assembling of the anti-vibration device  10  is completed (the anti-vibration device forming step). The partition member  15  is fitted to the molded body with the elastic partition membrane  16  stored between the pair of opposing walls thereof. 
         [0079]    As shown in  FIG. 6(   a ), in fixing (pressing-in) of the boss member  11  of the anti-vibration device  10  and the fixing member  31  of the second bracket  30 , the second bracket  30  is fixed to a table (not illustrated) of the press-in device, and the boss member  11  of the anti-vibration device  10  is held by a holding arm (not illustrated) of the press-in device and is disposed at a pressing-in possible position (that is, a position where the external shape of the extension section  11   c  and the shaft section  11   b  of the boss member  11  (refer to  FIG. 3(   a )) agrees to the external shape of the extension section press-fitting space  36  and the shaft section press-fitting space  37  of the press-fitting section  35  (refer to  FIG. 5(   a )) as viewed in the press-in direction). 
         [0080]    Also, the holding arm is formed into a U-shape in a top view (as viewed in the axis O direction), and holds the shaft section  11   b  of the boss member  11  on the inner peripheral surface of the U-shape. The inner peripheral surface dimension of the U-shape corresponds to the outer peripheral surface dimension of the shaft section  11   c , and the thickness dimension of the U-shape (the holding arm) is made smaller than the gap dimension between the upper surface of the fixing member  31  of the second bracket  30  and the lower surface of the base section  11   a  (the rubber membrane  13   a ) of the boss member  11 . 
         [0081]    From this state, the holding arm of the press-in device is moved toward the press-in direction (the direction orthogonal to the axis O) shown by the arrow A of  FIG. 6(   a ), and the extension section  11   c  and the shaft section  11   b  of the boss member  11  are pressed in to the extension section press-fitting space  36  and the shaft section press-fitting space  37  of the press-fitting section  35  through the opening in the side surface. The holding arm of the press-in device further moves, the press-in position of the extension section  11   c  and the shaft section  11   b  of the boss member  11  reaches a prescribed position as shown in  FIG. 6(   b ) and  FIG. 6(   c ), and thereby pressing-in (the second bracket fixing step) is completed. 
         [0082]    Thus, in the anti-vibration unit  1 , the boss member  11  of the anti-vibration device  10  is fixed (pressed in and fixed) to the fixing member  31  of the second bracket  30  by pressing-in, allowing the number of parts to be reduced as much as the bolts can be omitted, compared to the case where the boss member  11  of the anti-vibration device  10  is fixed (fastened and fixed) to the fixing member  31  of the second bracket  30  by bolts as in conventional products. 
         [0083]    Also, when the bolts can be omitted, it is not necessary to form female threaded sections for screwing the bolts in the boss member  11  of the anti-vibration device  10  (that is, to bore holes and to cut female threads on the inner peripheral surfaces thereof). Thus, the man-hours during manufacturing can be reduced correspondingly. Further, when the boss member  11  of the anti-vibration device  10  is to be chemically treated for vulcanizingly adhering the anti-vibration base  13 , it is not necessary to execute a step of protecting the female threaded sections with masking bolts. Therefore the work of attaching and detaching the masking bolts is not required, and the man-hours during manufacturing can be reduced correspondingly. Also, it is not necessary to prepare the masking bolts, and the manufacturing cost can be reduced correspondingly. 
         [0084]    Also, scraping chips generated in pressing-in can be discharged to the outside because the extension section press-fitting space  36  in the press-fitting section  35  of the fixing member  31  is formed so as to penetrate in the press-in direction (that is, to be opened in the side surfaces on both sides of the fixing member  31 ). 
         [0085]    Also, with respect to the anti-vibration unit  1 , the press-in section of the boss member  11  is formed into a T-shape in the front view (refer to  FIG. 3(   a )) in which the extension section  11   c  is extended outward in the radial direction from the projection distal end of the shaft section  11   b , a space corresponding to the external shape of the press-in section of the boss member  11  (the extension section press-fitting space  36  and the shaft section press-fitting space  37 ) is formed in the fixing member  31  of the second bracket  30 , and the press-in section of the boss member  11  is pressed in to the space in the direction orthogonal to the axis O through the opening in the side surface of the fixing member  31 . Therefore the boss member  11  of the anti-vibration device  10  can be securely fixed to the fixing member  31  of the second bracket  30 . 
         [0086]    That is, when the first bracket  20  is relatively displaced with respect to the second bracket  30  in the axis O direction (the vertical direction in  FIG. 1(   b )) of the anti-vibration device  10 , the extension section  11   c  in the press-in section of the boss member  11  engages with the inner wall surface of the space in the press-fitting section  35  (that is, the lower surface of the restriction wall  38 ), and the state the boss member  11  of the anti-vibration device  10  is fixed to the fixing member  31  of the second bracket  30  can be securely maintained. The same is true when relative displacement to the prying direction (the direction of inclining the axis O of the anti-vibration device  10 ) is combined thereto. 
         [0087]    On the other hand, even when the first bracket  20  is relatively displaced with respect to the second bracket  30  toward the direction orthogonal to the axis O of the anti-vibration device  10  and the direction parallel to the press-in direction (the direction vertical to the paper surface in  FIG. 1(   b ); the right/left direction in  FIG. 6(   b )) (that is, when the outer tube member  12  of the anti-vibration device  10  is displaced in parallel to the opposite direction of the press-in direction of the boss member  11  (the direction of the arrow A in  FIG. 6(   a ))) by the first bracket  20 , a force toward the direction making the extension section  11   c  incline (that is, the boss member  11  inclines and rotates the extension section  11   c ) is also generated by elastic deformation of the anti-vibration base  13 , because the anti-vibration base  13  is interposed between the outer tube member  12  and the boss member  11 , in the boss member  11 , and therefore the extension section  11   c  of the boss member  11  engages with the inner surface wall of the space in the press-fitting section  35  of the fixing member  31  (the bottom surface of the extension section press-fitting space  36  and the lower surface of the restriction wall  38 ). Thus, the press-in section of the boss member  11  can be prevented from slipping off from the press-fitting section  35  (the extension section press-fitting space  36  and the shaft section press-fitting space  37 ) of the fixing member  31 . Therefore, a state the boss member  11  of the anti-vibration device  10  is fixed to the fixing member  31  of the second bracket  30  can be securely maintained. 
         [0088]    Next, an anti-vibration unit  201  in a second embodiment will be described referring to  FIG. 7  and  FIG. 8 . Although, in the first embodiment, a case was described where the extension section press-fitting space  36  and the shaft section press-fitting space  37  of the press-fitting section  35  were formed so as to penetrate in the press-in direction (that is, the openings were provided in both side surfaces of the press-fitting section  35 ), in a press-fitting section  235  in the second embodiment, a positioning wall  239  is formed, thus the extension section press-fitting space  36  and the shaft section press-fitting space  37  are made not to penetrate in the press-in direction. Also, with respect to the same portions as those of the first embodiment described above, the same reference signs will be given, and the description thereof will be omitted. 
         [0089]      FIG. 7(   a ) is a partially enlarged front view of a second bracket  230  in the second embodiment,  FIG. 7(   b ) is a partially enlarged cross-sectional view of the second bracket  230  taken from the line VIIb-VIIb of  FIG. 7(   a ), and  FIG. 7(   c ) is a partially enlarged top view of the second bracket  230  as viewed from the direction of the arrow VIIc of  FIG. 7(   a ). Also,  FIG. 7(   a ) corresponds to the front view of  FIG. 5(   a ), and  FIG. 7(   b ) corresponds to the cross-sectional view of  FIG. 5(   b ). 
         [0090]    As shown in  FIG. 7 , in the second embodiment, on one end side (the left side in  FIG. 7(   b )) in the press-in direction of the extension section press-fitting space  36  and the shaft section press-fitting space  37 , the positioning wall  239  is formed. The positioning wall  239  is a portion for positioning the press-in position of the boss member  11  pressed in to the extension section press-fitting space  36  and the shaft section press-fitting space  37 , and is formed as a plate-like wall section that blocks one of the openings of the spaces  36 ,  37 . Therefore, in the second embodiment, the press-fitting section  235  includes an opening of the extension section press-fitting space  36  and the shaft section press-fitting space  37  only in the other side surface of a fixing member  231  that is on the opposite side of the positioning wall  239 . Also, in the positioning wall  239 , the surface on the side facing the both spaces  36 ,  37  (the right side surface in  FIG. 7(   b )) is formed as a flat surface that is parallel to the axis O. 
         [0091]      FIG. 8(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  201  before pressing-in,  FIG. 8(   b ) is a partially enlarged cross-sectional view of the anti-vibration unit  201  after pressing-in, and  FIG. 8(   c ) is a partially enlarged front view of the anti-vibration unit  201  after pressing-in.  FIG. 8(   a ) and  FIG. 8(   b ) correspond to  FIG. 6(   a ), and  FIG. 8(   c ) corresponds to  FIG. 1(   b ). 
         [0092]    As shown in  FIG. 8(   a ), in fixing (pressing-in) of the boss member  11  of the anti-vibration device  10  and the fixing member  231  of the second bracket  230 , similarly to the case of the first embodiment, the second bracket  230  is fixed to a table (not illustrated) of the press-in device, and the boss member  11  of the anti-vibration device  10  is held by a holding arm (not illustrated) of the press-in device and is disposed at a pressing-in possible position. 
         [0093]    From this state, the holding arm of the press-in device is moved toward the press-in direction (the direction orthogonal to the axis O), and the press-in section (the extension section  11   c  and the shaft section  11   b ) of the boss member  11  is pressed in to the extension section press-fitting space  36  and the shaft section press-fitting space  37  of the press-fitting section  235  through the opening in the side surface of the fixing member  231 . When the holding arm of the press-in device is further moved to the press-in direction, the positioning wall  239  is made to abut upon the press-in section of the boss member  11 , and movement (pressing-in) in the press-in direction is restricted by the abutment. As a result, as shown in  FIG. 8(   a ) and  FIG. 8(   b ), the press-in section of the boss member  11  reaches a prescribed press-in position, and pressing-in (the second bracket fixing step) is completed. 
         [0094]    Also, whether or not the press-in section of the boss member  11  has abutted upon the positioning wall  239  is determined by whether or not the press-in load measured by a load sensor (a load cell and the like, for example) arranged on the holding arm of the press-in device has exceeded a reference value. 
         [0095]    Thus, in the second embodiment, the press-in position can be positioned by pressing in the press-in section of the boss member  11  to the position of abutting upon the positioning wall  239 . Therefore, for example, in comparison to a case where the press-in position of the boss member  11  to the fixing member  231  is managed by the stroke amount of the holding arm of the press-in device, the press-in step can be simplified to reduce the control cost thereof, and the positional accuracy of the press-in position can be improved by preventing the press-in position from being dispersed. 
         [0096]    Also, in a product state where pressing-in of the boss member  11  has been completed, the anti-vibration unit  201  is brought into a state where the press-in section of the boss member  11  abuts upon the positioning wall  239  of the press-fitting section  235  (that is, the state the positioning wall  239  supports the press-in section of the boss member  11 ), and therefore, when the first bracket  20  is relatively displaced with respect to the second bracket  30 , the input load can be counteracted utilizing engagement of the press-in section of the boss member  11  and the positioning wall  239 . Accordingly, the state the press-in section of the boss member  11  is fixed (pressed in) to the press-fitting section  235  of the fixing member  231  can be securely maintained. 
         [0097]    Next, an anti-vibration unit  301  in a third embodiment will be described referring to  FIG. 9  and  FIG. 10 . Although, in the second embodiment, a case was described where the entire surface on the side facing the extension section press-fitting space  36  and the shaft section press-fitting space  37  of the positioning wall  239  was formed as a flat surface, in a positioning wall  339  in the third embodiment, a groove section  339   a  of a recessed groove shape is recessively arranged in a part of the surface on the side facing the extension section press-fitting space  36  and the shaft section press-fitting space  37 . Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0098]      FIG. 9(   a ) is a partially enlarged cross-sectional view of a second bracket  330  in the third embodiment, and  FIG. 9(   b ) is a partially enlarged rear view of the second bracket  330  as viewed from the direction of the arrow IXb of  FIG. 9(   a ).  FIG. 9(   b ) corresponds to the cross-sectional view of  FIG. 5(   b ). 
         [0099]    As shown in  FIG. 9 , in the positioning wall  339  in the third embodiment, the groove section  339   a  is recessively arranged in the surface facing the extension section press-fitting space  36  and the shaft section press-fitting space  37  (the right side surface in  FIG. 9(   a ); that is, the surface on the side upon which the press-in section of the boss member  11  abuts). The positioning wall  339  has the same configuration as that of the positioning wall  239  in the second embodiment except for the presence/absence of the groove section  339   a , and description thereof will be omitted. 
         [0100]    The groove section  339   a  is a recessed groove for storing the scraping chips in pressing-in (the scraping chips generated after the outer wall surface of the press-in section or the inner wall surface of a press-fitting section  335  is scraped when the press-in section of the boss member  11  is pressed in to the press-fitting section  335  of a fixing member  331 ), and is extended along the outer periphery that continues to the inner wall surface of the press-fitting section  335  in the surface facing the extension section press-fitting space  36  and the shaft section press-fitting space  37  (the right side surface in  FIG. 9(   a )). 
         [0101]    In the present embodiment, the groove section  339   a  is extended only by the width (the width in the right/left direction in  FIG. 9(   b ) and  FIG. 9(   c )) equal to that of the bottom surface (the lower surface in  FIG. 9(   a ) and  FIG. 9(   b )) forming the extension section press-fitting space  36  out of the inner wall surface of the press-fitting section  335  along the outer periphery that continues to the bottom surface. Also, the cross-sectional shape of the groove section  339   a  is made into a semicircular shape, and smoothly continues to the bottom surface that forms the extension section press-fitting space  36 . 
         [0102]      FIG. 10(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  301  after pressing-in, and  FIG. 10(   b ) is a partially enlarged front view of the anti-vibration unit  301  after pressing-in.  FIG. 10(   a ) corresponds to  FIG. 6(   a ), and  FIG. 10(   b ) corresponds to  FIG. 1(   b ). 
         [0103]    In fixing (pressing-in) of the boss member  11  of the anti-vibration device  10  and the fixing member  331  of the second bracket  330 , similarly to the case of the second embodiment, the second bracket  330  is fixed to a table (not illustrated) of the press-in device, the boss member  11  of the anti-vibration device  10  is held by a holding arm (not illustrated) of the press-in device, the holding arm of the press-in device is moved to the press-in direction, and thereby the press-in section (the extension section  11   c  and the shaft section  11   b ) of the boss member  11  are pressed in to the position abutting upon a positioning wall  339  as shown in  FIG. 10 . 
         [0104]    In this case, in the positioning wall  339 , the groove section  339   a  is recessively arranged in the surface on the side upon which the press-in section of the boss member  11  abuts, and therefore, when scraping chips are generated in pressing in the press-in section of the boss member  11  to the press-fitting section  335  of the fixing member  331 , the scraping chips can be stored in the groove section  339   a . That is, when the scraping chips are caught between the press-in section of the boss member  11  and the positioning wall  339 , dispersion occurs in the press-in position (the position in the right/left direction in  FIG. 9(   a )) of the boss member  11 . However, according to the anti-vibration unit  301 , the scraping chips can be stored in the groove section  339   a , the press-in section of the boss member  11  can be tightly attached to the positioning wall  339 , and therefore the positional accuracy of the press-in position of the boss member  11  can be secured. 
         [0105]    Also, in the third embodiment, the groove section  339   a  is formed only in the outer periphery on the lower side of the positioning wall  339  (that is, the outer periphery continuing to the bottom surface side of the extension section press-fitting space  36 ). Therefore, while the strength of the positioning wall  339  is secured with the formation region of the groove section  339   a  as the required minimum, the scraping chips generated by pressing-in and dropped on the bottom surface of the extension section press-fitting space  36  can be efficiently stored in the groove section  339   a . Also, stress concentration can be inhibited and the strength of the positioning wall  339  can be secured because the groove section  339   a  is formed as a recessed groove with a semicircular cross section. 
         [0106]    Next, an anti-vibration unit  401  in a fourth embodiment will be described referring to  FIG. 11 . Although a case where the shaft section  11   b  and the extension section  11   c  of the boss member  11  exposed the outer wall surface in the first embodiment was described, the outer wall surfaces of the shaft section  11   b  and the extension section  11   c  of the boss member  11  in the fourth embodiment are covered by a rubber membrane  413   a . With respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0107]      FIG. 11(   a ) is a partially enlarged cross-sectional view of an anti-vibration unit  401  after pressing-in in the fourth embodiment, and  FIG. 11(   b ) is a partially enlarged front view of the anti-vibration unit  401  after pressing-in.  FIG. 11(   a ) corresponds to  FIG. 6(   a ), and  FIG. 11(   b ) corresponds to  FIG. 1(   b ). 
         [0108]    With respect to an anti-vibration device  410  in the fourth embodiment, in addition to that the shaft section  11   b  of the boss member  11  is covered by the rubber membrane  13   a , the entire outer wall surface of the shaft section  11   b  and the extension section  11   c  is covered by the rubber membrane  413   a  that continues to the anti-vibration base  13  through the rubber membrane  13   a . Thus, in manufacturing the anti-vibration device  410 , the work of removing the rubber burr attached to the outer wall surface of the boss member  11  can be omitted as in the case of the first embodiment, and therefore the man-hours can be reduced. Also, the required accuracy of the sealing performance of the vulcanizing mold can be made loose, because the entire boss member  11  is configured to be covered by the rubber membrane  13   a ,  413   a , compared with the case of the first embodiment, and therefore the manufacturing cost can be reduced correspondingly. 
         [0109]    Next, an anti-vibration unit  501  in a fifth embodiment will be described referring to  FIG. 12  and  FIG. 13 . Although a case where the extension section  11   c  of the boss member  11  was formed into a rectangular shape (refer to  FIG. 3(   b )) as viewed in the axis O direction was described in the first embodiment, an extension section  511   c  in the fifth embodiment is formed into a circular shape as viewed in the axis O direction. Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0110]      FIG. 12(   a ) is a partially enlarged front view of an anti-vibration device  510  in the fifth embodiment, and  FIG. 12(   b ) is a cross-sectional view of a boss member  511  taken from the line XIIb-XIIb of  FIG. 12(   a ).  FIG. 12(   a ) corresponds to the front view of the anti-vibration device  10  as viewed from the direction of the arrow IIIa of  FIG. 2 . 
         [0111]    As shown in  FIG. 12 , the boss member  511  in the fifth embodiment is formed so that the extension section  511   c  extends in a flange shape from the projection distal end of the shaft section  11   b  outward in the radial direction (the direction orthogonal to the axis O). With respect to the boss member  511 , similarly to the case of the first embodiment, a part of the shaft section  11   b  and the extension section  511   c  are made to be the press-in section that is pressed in to the press-fitting section  35  of the second bracket  30 . 
         [0112]    The extension section  511   c  is constant in the thickness dimension (the dimension in the vertical direction in  FIG. 12(   a )), is formed into a disk shape that is circular as viewed in the axis O direction, and is disposed so as to be concentric with the shaft section  11   b . Therefore, the boss member  511  is formed into a shape that is symmetric around the axis O. Also, in a front view shown in  FIG. 12(   a ), the press-in section (the shaft section  11   b  and the extension section  511   c ) of the boss member  511  comes to have a generally T-shape. 
         [0113]    Also, the shape in the front view shown in  FIG. 12(   a ) of the boss member  511  is formed to have equal dimensions with those of the shape in the front view shown in  FIG. 3(   a ) of the boss member  11  in the first embodiment. In this case, the diameter dimension as viewed in the axis 0 direction of the extension section  511   c  is made smaller than the width dimension (the right/left direction in  FIG. 13(   a )) of the press-fitting section  35  (the extension section press-fitting space  36  and the shaft section press-fitting space  37 ) of the second bracket  30 . 
         [0114]      FIG. 13(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  501  after pressing-in, and  FIG. 13(   b ) is a partially enlarged front view of the anti-vibration unit  501  after pressing-in.  FIG. 13(   a ) corresponds to  FIG. 6(   a ), and  FIG. 13(   b ) corresponds to  FIG. 1(   b ). 
         [0115]    In fixing (pressing-in) of the boss member  511  of the anti-vibration device  510  and the fixing member  31  of the second bracket  30 , similarly to the case of the first embodiment, the second bracket  30  is fixed to a table (not illustrated) of the press-in device, and the boss member  511  of the anti-vibration device  510  is held by a holding arm (not illustrated) of the press-in device, the holding arm of the press-in device is moved to the press-in direction, and thereby the press-in section (the extension section  511   c  and the shaft section  11   b ) of the boss member  511  is pressed in to a prescribed press-in position as shown in  FIG. 13 . 
         [0116]    Thus, with respect to the anti-vibration unit  501  in the fifth embodiment, it is not necessary to consider the orientation in the peripheral direction because the extension section  511   c  of the boss member  511  is formed into a disk shape that is concentric with the shaft section  11   b . Therefore, in arranging the boss member  511  into the vulcanizing mold at the time of vulcanizing molding of the anti-vibration base  13 , the work can be executed without considering the orientation around the axis O of the boss member  511  at the time of arranging the same. Similarly, in pressing in the outer tube member  12  of the anti-vibration device  510  to the press-in hole of the first bracket  20  in the axis O direction for holding (the first bracket holding step; refer to  FIG. 2 ), the work can be executed without considering the orientation around the axis O of the anti-vibration device  510  at the time of pressing in the same. That is, the work of positioning the boss member  511  or the anti-vibration device  510  in the peripheral direction can be omitted, and the man-hours during manufacturing can be reduced correspondingly. 
         [0117]    Also, by forming the extension section  511   c  of the boss member  511  into a disk shape of a circular shape as viewed in the axis O direction, the engagement area between such the extension section  511   c  and the inner wall surface in the extension section press-fitting space  36  of the press-fitting section  35  (the bottom surface of the extension section press-fitting space  36  and the lower surface of the restriction wall  38 ) can be enlarged. Thus, as described above, even when the first bracket  20  is relatively displaced with respect to the second bracket  30 , by utilizing engagement of the extension section  511   c  and the inner wall surface of the extension section press-fitting space  36 , the press-in section of the boss member  511  can be prevented from slipping off from the press-fitting section  35  (the extension section press-fitting space  36  and the shaft section press-fitting space  37 ) of the fixing member  31 . Therefore, a state the boss member  511  of the anti-vibration device  510  is fixed to the fixing member  31  of the second bracket  30  can be securely maintained. 
         [0118]    Next, an anti-vibration unit  601  in a sixth embodiment will be described referring to  FIG. 14  and  FIG. 15 . In the anti-vibration unit  601  in the sixth embodiment, with respect to the anti-vibration unit  501  in the fifth embodiment, a positioning wall  639  is arranged in the extension section press-fitting space  36  and the shaft section press-fitting space  37  of a press-fitting section  635 . The anti-vibration unit  601  in the sixth embodiment and the anti-vibration unit  501  in the fifth embodiment are different from each other only in presence/absence of the positioning wall  639  and are the same with respect to the rest, therefore description thereof will be omitted. Further, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0119]      FIG. 14(   a ) is a partially enlarged front view of a second bracket  630  in the sixth embodiment,  FIG. 14(   b ) is a partially enlarged cross-sectional view of the second bracket  630  taken from the line XIVb-XIVb in  FIG. 14(   a ), and  FIG. 14(   c ) is a partially enlarged cross-sectional view of the second bracket  630  taken from the line XIVc-XIVc in  FIG. 14(   b ).  FIG. 14(   a ) corresponds to  FIG. 5(   a ), and  FIG. 14(   b ) corresponds to the cross-sectional view of  FIG. 5(   b ). 
         [0120]    As shown in  FIG. 14 , in the press-fitting section  635  in the sixth embodiment, the positioning wall  639  is formed. The positioning wall  639  is a portion for positioning the press-in position of the boss member  511  pressed in to the extension section press-fitting space  36  and the shaft section press-fitting space  37 , and is formed as a wall section that blocks an opening on one end side (the left side in  FIG. 14(   b )) in the press-in direction of the extension section press-fitting space  36  on the one end side. Also, in the present embodiment, the positioning wall  639  is not formed in the shaft section press-fitting space  37 , and the cross-sectional shape of the shaft section press-fitting space  37  is made constant along the press-in direction (the right/left direction in  FIG. 14(   b ). 
         [0121]    With respect to the positioning wall  639 , the surface on the side facing the extension section press-fitting space  36  (the right side surface in  FIG. 14(   b ), that is, the surface on the side the press-in section (the extension section  511   c ) of the boss member  11  abuts upon) is formed into a state curving in an arc shape in the top view and recessed as shown in  FIG. 14(   c ). The arc shape in this top view is formed corresponding to (that is, with an equal diameter dimension) the circular shape as viewed in the axis O direction in the extension section  511   c  of the boss member  511  (refer to  FIG. 12(   b )). 
         [0122]    In the center in the width direction (the right/left direction in  FIG. 14(   a )) of the positioning wall  639 , an opening  639   a  of a slit shape is formed. The opening  639   a  is an opening for discharging the scraping chips generated in pressing-in to the outside, the upper end side (the upper side in  FIG. 14(   a )) is made to communicate with the shaft section press-fitting space  37 , and the lower end side (the lower side in  FIG. 14(   a )) continues to the bottom surface of the extension section press-fitting space  36  (the inner wall surface of the press-fitting section  635 ). 
         [0123]      FIG. 15(   a ) is a partially enlarged front view of the anti-vibration unit  601  after pressing-in, and  FIG. 15(   b ) is a partially enlarged cross-sectional view of the anti-vibration unit  601  taken from the line XVb-XVb of  FIG. 15(   a ).  FIG. 14(   a ) corresponds to  FIG. 1(   b ). 
         [0124]    In fixing (pressing-in) of the boss member  511  of the anti-vibration device  510  and a fixing member  631  of the second bracket  630 , similarly to the case of the fifth embodiment, the second bracket  630  is fixed to a table (not illustrated) of the press-in device, and the boss member  511  of the anti-vibration device  510  is held by a holding arm (not illustrated) of the press-in device and is disposed at a pressing-in possible position. 
         [0125]    From this state, the holding arm of the press-in device is moved toward the press-in direction (the direction orthogonal to the axis O), and the press-in sections (the extension section  511   c  and a shaft section  511   b ) of the boss member  511  are pressed in to the extension section press-fitting space  36  and the shaft section press-fitting space  37  of the press-fitting section  635  through the opening in the side surface of the fixing member  631 . When the holding arm of the press-in device is further moved to the press-in direction, the positioning wall  639  is made to abut upon the press-in section (the extension section  511   c ) of the boss member  511 , and movement (pressing-in) in the press-in direction is restricted by the abutment. As a result, as shown in  FIG. 14(   a ) and  FIG. 14(   b ), the press-in section of the boss member  511  comes to reach a prescribed press-in position, and pressing-in (the second bracket fixing step) is completed. 
         [0126]    Thus, in the sixth embodiment, by pressing in the press-in section of the boss member  511  to the position for abutting upon the positioning wall  639 , the press-in position can be positioned. Therefore, the press-in step can be simplified to reduce the control cost the press-in section, and the positional accuracy of the press-in position can be improved by preventing the press-in position from being dispersed. Also, in a product state after pressing-in, the input load can be counteracted utilizing engagement of the press-in section (the extension section  511   c ) of the boss member  511  and the positioning wall  639 . Therefore a state the press-in section of the boss member  511  is fixed (pressed in) to the press-fitting section  635  of the fixing member  631  can be securely maintained. 
         [0127]    In this case, the width dimension (the dimension in the vertical direction in  FIG. 15(   b )) of the press-fitting section  635  is prevented from increasing and the second bracket  630  can be miniaturized while positioning of the press-in position of the boss member  511  is enabled because the positioning wall  639  is formed so as to curve in an arc shape in the top view as shown in  FIG. 15(   b ). Also, when the extension section  511   c  of the boss member  511  is formed into a square shape as viewed in the axis O direction for example, in order to suppress the width dimension of the press-fitting section  635 , it is necessary to make the entire positioning wall thin. However, when the positioning wall can be made to curve in an arc shape as in the present embodiment, both ends of the positioning wall  639  can be made thick, and the stiffness thereof can be secured. 
         [0128]    Also, when scraping chips are generated in pressing in the boss member  511  to the press-fitting section  635 , the scraping chips can be discharged to the outside through the opening  639   a  because the opening  639   a  is formed in the positioning wall  639 . Thus, the scraping chips can be prevented from being caught, the press-in section (the extension section  511   c ) of the boss member  511  can be tightly attached to the positioning wall  639 , and therefore the positional accuracy of the press-in position of the boss member  511  can be secured. 
         [0129]    Here, the plate width (the dimension in the vertical direction in  FIG. 15(   b )) of the center part in the width direction (the right/left direction in  FIG. 15(   b )) becomes thin because the positioning wall  639  is formed so as to curve in an arc shape in the top view as described above. In this case, unless the opening  639   a  is arranged, it is necessary to increase the plate thickness of the positioning wall  639  (the center part in the width direction) in order to secure the strength (to prevent breakage) of the center part in the width direction in restricting the press-in position of the boss member  511 , and the second bracket  630  (the fixing member  631 ) becomes large correspondingly. On the other hand, in the present embodiment, the second bracket  630  (the fixing member  631 ) can be miniaturized while securing the strength (preventing breakage of the center part in the width direction) of the positioning wall  639  because the opening  639   a  is formed in the center part in the width direction of the positioning wall  639 . 
         [0130]    Next, an anti-vibration unit  701  in a seventh embodiment will be described referring to  FIG. 16  to  FIG. 18 . In the first embodiment, a case was described where the press-in section of the anti-vibration device  10  was pressed in the direction orthogonal to the axis O with respect to the press-fitting section  35  of the second bracket  30 . However, in an anti-vibration device  710  in the seventh embodiment, the press-in section thereof is pressed in the axis O direction with respect to a press-fitting section  735  of a second bracket  730 . With respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0131]      FIG. 16(   a ) is a partially enlarged front view of an anti-vibration device  710  in the seventh embodiment, and  FIG. 16(   b ) is a cross-sectional view of a boss member  711  taken from the line XVIb-XVIb of  FIG. 16(   a ).  FIG. 16(   a ) corresponds to  FIG. 3(   a ). 
         [0132]    As shown in  FIG. 16 , the boss member  711  is formed so that a shaft section  711   b  projects downward from the base section  11   a . The shaft section  711   b  is formed as a shaft-like body with a circular cross section, and the cross-sectional area thereof is made constant along the axis O. In the seventh embodiment, this shaft section  711   b  is the press-in section which is pressed in to the press-fitting section  735  (refer to  FIG. 17 ) of the second bracket  730 . 
         [0133]      FIG. 17(   a ) is a partially enlarged front view of the second bracket  730 , and  FIG. 17(   b ) is a partially enlarged top view of the second bracket  730  as viewed from the arrow XVIIb of  FIG. 17(   a ).  FIG. 17(   a ) corresponds to  FIG. 5(   a ). 
         [0134]    As shown in  FIG. 17 , the press-fitting section  735  in a fixing member  731  of the second bracket  730  includes a shaft section press-fitting space  737 . The shaft section press-fitting space  737  is a space where the shaft section  711   b  (refer to  FIG. 16 ) in the boss member  711  of the anti-vibration device  710  is pressed in, and is penetratingly formed as a through hole with a circular cross section in the press-fitting section  735  of the fixing member  731 . The inside diameter dimension of the shaft section press-fitting space  737  is made smaller than the outside diameter dimension of the shaft section  711   b  of the boss member  711 , and the press-in allowance at the time of pressing-in is secured. 
         [0135]      FIG. 18(   a ) is a partially enlarged front view of the anti-vibration unit  701  after pressing-in, and  FIG. 18(   b ) is a partially enlarged cross-sectional view of the anti-vibration unit  701  taken from the line XVIIIb-XVIIIb of  FIG. 18(   a ). 
         [0136]    In manufacturing the anti-vibration unit  701 , the anti-vibration device  710  (the outer tube member  12 ) is pressed in to and held by the first bracket  20  (the first bracket holding step; refer to  FIG. 2 ), the stopper rubber SG (refer to  FIG. 1 ) is furnished, the boss member  711  (the press-in section) of the anti-vibration device  710  is thereafter fixed by being pressed in to the fixing member  731  (the press-fitting section  735 ) of the second bracket  730  (the second bracket fixing step; refer to  FIG. 18 ), and thereby manufacturing of the anti-vibration unit  701  is completed. 
         [0137]    In fixing (pressing-in) of the boss member  711  of the anti-vibration device  710  and the fixing member  731  of the second bracket  730 , first, the second bracket  730  is fixed to a table (not illustrated) of the press-in device, the boss member  711  of the anti-vibration device  710  is held by a first holding arm (not illustrated) of the press-in device, and the first bracket  20  is held by a second holding arm (not illustrated) of the press-in device. Then, the first holding arm and the second holding arm are relatively moved in the axis O direction of the anti-vibration device  710 , and the anti-vibration device  710  (the anti-vibration base  13 ) is compressively deformed in the axis O direction. 
         [0138]    While maintaining this compressively deformed state, the first and second arms are moved in parallel, the anti-vibration device  710  is fit within the frame of the second bracket  730 , and is disposed at the pressing-in possible position (that is, the position where the center (the axis O) of the shaft section  711   b  of the boss member  711  agrees to the center of the shaft section press-fitting space  737  of the press-fitting section  735  as viewed in the press-in direction). 
         [0139]    From this state, the first holding arm of the press-in device is moved toward the press-in direction (the axis 0 direction), and the shaft section  711   b  of the boss member  711  is pressed in to the shaft section press-fitting space  737  of the press-fitting section  735 . The first holding arm of the press-in device is further moved, the press-in position of the shaft section  711   b  of the boss member  711  reaches a prescribed position as shown in  FIG. 18(   a ) and  FIG. 18(   b ), and thereby pressing-in (the second bracket fixing step) is completed. 
         [0140]    With the anti-vibration unit  701  pressed in to the prescribed position (the product state), the upper end side of the anti-vibration device  710  is made to abut upon the lower surface side of the connection member  33  of the second bracket  730  (refer to  FIG. 1(   b )). 
         [0141]    With respect to the anti-vibration unit  701  in the seventh embodiment, it is not necessary to consider the orientation in the peripheral direction because the boss member  711  is formed into a symmetric shape around the axis O. Therefore, in arranging the boss member  711  into the vulcanizing mold at the time of vulcanizing molding of the anti-vibration base  13 , the work can be executed without considering the orientation around the axis O of the boss member  711  at the time of arranging the same. Similarly, in pressing in the outer tube member  12  of the anti-vibration device  710  to the press-in hole of the first bracket  20  in the axis O direction for holding the outer tube member  12  (the first bracket holding step; refer to  FIG. 2 ), the work can be executed without considering the orientation around the axis O of the anti-vibration device  710  at the time of pressing in the same. That is, the work for positioning the boss member  711  or the anti-vibration device  710  in the peripheral direction can be omitted, and the man-hours during manufacturing can be reduced correspondingly. 
         [0142]    Also, when scraping chips are generated in pressing in the boss member  711  to the press-fitting section  735 , the scraping chips can be discharged to the outside through an opening on the lower surface side (the lower side in  FIG. 18(   b )) of the shaft section press-fitting space  737  because the shaft section press-fitting space  737  of the press-fitting section  735  is formed as a through hole. Thus, the press-in section (the shaft section  711   b ) of the boss member  711  can be pressed in to the prescribed position without being interfered by the scraping chips, and the positional accuracy of the press-in position of the boss member  711  can be secured. 
         [0143]    Next, an anti-vibration unit  801  in an eighth embodiment will be described referring to  FIG. 19 . In the first embodiment, a case was described where, when the press-in section of the anti-vibration device  10  was pressed in to the press-fitting section  35  of the second bracket  30 , the upper end side (the opposite side of the press-in section) of the anti-vibration device  10  was fit within the frame (below the lower surface of the connection member  33 ) of the second bracket  30  (that is, a case where pressing-in is possible even if the anti-vibration device  10  is not compressively deformed in the axis O direction). However, with respect to the anti-vibration unit  801  in the eighth embodiment, the upper end side (the opposite side of the press-in section) of an anti-vibration device  810  is not fit within the frame (below the lower surface of the connection member  33 ) of the second bracket  30  in pressing in the press-in section of the anti-vibration device  810  to the press-fitting section  35  of the second bracket  30 , therefore it is necessary to compressively deform the anti-vibration device  810  in the axis O direction. Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0144]      FIG. 19  is a cross-sectional view of the anti-vibration unit  801  in the eighth embodiment, and a state before pressing-in is illustrated.  FIG. 19  corresponds to  FIG. 6(   a ). 
         [0145]    The anti-vibration unit  801  in the eighth embodiment is different from the anti-vibration unit  1  in the first embodiment only in that the anti-vibration device  810  is different from the anti-vibration device  10  in the first embodiment. More specifically, in the anti-vibration device  810 , the leg length of an anti-vibration base  813  is made longer than the leg length of the anti-vibration base  13  of the anti-vibration device  10  in the first embodiment, and the height dimension (the height in the axis O direction) of the anti-vibration device  810  is made larger than the height dimension of the anti-vibration device  10 . Configurations except for the anti-vibration base  813  are the same between the anti-vibration devices  10  and  810 , and description thereof will be omitted. 
         [0146]    As shown in  FIG. 19 , in manufacturing the anti-vibration unit  801 , the anti-vibration device  810  (the outer tube member  12 ) is pressed in to and held by the first bracket  20  (the first bracket holding step; refer to  FIG. 2 ), the stopper rubber SG (refer to  FIG. 1 ) is furnished, the boss member  11  (the press-in section) of the anti-vibration device  810  is thereafter fixed by being pressed in to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  (the second bracket fixing step; refer to  FIGS. 18 ), and thereby manufacturing of the anti-vibration unit  801  is completed. 
         [0147]    Here, with respect to the anti-vibration device  810  of the anti-vibration unit  801 , the upper end side (the opposite side of the press-in section) of the anti-vibration device  810  is not fit within the frame (below the lower surface of the connection member  33 ) of the second bracket  30  when pressing in because the height dimension of the anti-vibration device  810  is large. In this case, it is possible to compressively deform the anti-vibration device  810  (the anti-vibration base  813 ) in the axis O direction and to press in by holding the boss member  11  of the anti-vibration device  810  by the first holding arm of the press-in device, holding the first bracket  20  by the second holding arm of the press-in device, and relatively moving these first holding arm and second holding arm in the axis O direction of the anti-vibration device  810 . 
         [0148]    However, in this method, it is necessary to use a press-in device in which the first holding arm and the second holding arm can generate the load not only in the press-in direction but also in the direction (the axis O direction) orthogonal to the press-in direction and movement in the press-in direction (the direction orthogonal to the axis O direction) is possible while maintaining a state where the load is generated in such direction, and the facility cost increases. Also, a step of compressively deforming the anti-vibration device  810  in the axis O direction is required before the press-in step, and the man-hours increase. 
         [0149]    On the other hand, in the present embodiment, as described below, by pressing in the boss member  11  (the press-in section) of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  using a press-in jig IJ, reduction of the facility cost and reduction of the man-hours are achieved. 
         [0150]    That is, in the present embodiment, as shown in  FIG. 19 , with the press-in jig IJ arranged in the press-in side opening of the second bracket  30  side by side, these second bracket  30  and the press-in jig IJ are fixed to a table (not illustrated) of the press-in device. The press-in jig IJ is for executing the compression motion of deforming the anti-vibration device  810  in the axis O direction at the time of press-in motion simultaneously (serving for two purposes), and is formed of an iron and steel material into a frame shape corresponding to the second bracket  30 . 
         [0151]    The press-in jig IJ includes an inclined surface IJa for guiding the boss member  11 . The inclined surface IJa is a flat surface having a width dimension equal to the width dimension (the dimension in the direction vertical to the paper surface in  FIG. 19 ) of the bottom surface (the lower surface in  FIG. 19 ) of the extension section press-fitting space  36  in the press-fitting section  35  of the second bracket  30 , and is configured so that the final end side (the left side in  FIG. 19 ) smoothly continues to the bottom surface of the extension section press-fitting space  36  where the jig IJ is fixed to the table of the press-in device and so as to incline downward from the final end side to the starting end side. 
         [0152]    Pressing-in of the boss member  11  (the press-in section) of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  is executed by holding the first bracket  20  by the first arm of the press-in device, holding the boss member  11  of the anti-vibration device  810  by the second arm of the press-in device, and moving these first arm and second arm in the press-in direction (the direction orthogonal to the axis O). The second arm is configured similarly to the holding arms described above. 
         [0153]    Here, in the press-in device used in the present embodiment, the first arm is formed so as to be movable only in the press-in direction (the direction orthogonal to the axis O), and, in pressing-in, restricts the outer tube member  12  from moving in a direction other than the press-in direction (for example, moving in the axis O direction, and inclining with respect to the axis O direction). On the other hand, the second arm is formed so as to be movable in the press-in direction (the direction orthogonal to the axis O), is formed so as to passively move in the direction (the axis O direction) orthogonal to the press-in direction. In pressing-in, although the boss member  11  of the anti-vibration device  810  is allowed to move in the direction (the axis O direction) orthogonal to the press-in direction, the second arm restricts movement in another direction (other than the press-in direction) (for example, inclining with respect to the axis O direction). 
         [0154]    Therefore, from a state shown in  FIG. 19 , by movement of the first arm and the second arm to the press-in direction (leftward in  FIG. 19 ), the boss member  11  of the anti-vibration device  810  is made to abut upon the inclined surface IJa of the press-in jig IJ, and these first arm and second arm are further moved to the press-in direction. Thus, while the outer tube member  12  held by the first arm is moved horizontally to the press-in direction along with the first arm, the boss member  11  held by the second arm is guided on the inclined surface IJa of the press-in jig IJ, is thereby moved to the press-in direction while rising in the axis O direction along with the second arm along the inclined surface IJa (that is, while compressively deforming the anti-vibration device  810  in the axis O direction), and is pressed in to the press-fitting section  35  in the fixing member  31  of the second bracket  30  upon going beyond the final end of the inclined surface IJa. 
         [0155]    Thus, with respect to the press-in device, by applying only the load toward the press-in direction (the direction orthogonal to the axis O) of the anti-vibration device  810  by the first arm and the second arm, the lower surface of the press-in section (the extension section  11   c ) of the boss member  11  is slid along the inclined surface IJa, and thereby the boss member  11  of the anti-vibration device  810  can be fixed to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  with the anti-vibration base  813  of the anti-vibration device  810  compressed in the axis O direction. That is, the step of pressing in the boss member  11  of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  for fixing and the step for compressing the anti-vibration device  810  in the axis O direction can be effected simultaneously. Thus, execution of the step of compressing the anti-vibration device  810  in the axis O direction separately from the press-in step is not required, and the man-hours during manufacturing can be reduced. Also, the structure of the press-in device can be simplified, and the facility cost for pressing in the boss member  811  of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  can be reduced. 
         [0156]    The present invention has been described above based on the embodiments. However, it can be easily presumed that the present invention is not limited to the embodiments described above, and a variety of improvements and alterations are possible within the scope not departing from the objects of the present invention. 
         [0157]    The figures cited in the respective embodiments described above are only an example, and it is naturally possible to employ other figures. Also, in the respective embodiments described above, the drawings are simplified, and, respective configurations are illustrated schematically in order to facilitate understanding. Therefore, it is naturally possible to change the scale of the respective configurations (for example, to increase or decrease the thickness dimension of the rubber membrane  13   a ,  413   a ). 
         [0158]    In the respective embodiments described above, although a case where the extension section  11   c ,  511   c  was formed into a rectangular shape in the front view was described, the present invention is not necessarily limited to it, and an inclined surface may be arranged in a part in the shape in the front view. An example of this aspect will be described as a modification of the fifth embodiment referring to  FIG. 20  and  FIG. 21 . Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0159]      FIG. 20(   a ) is a partially enlarged front view of the anti-vibration device  510  in the modification, and  FIG. 20(   b ) is a bottom view of the boss member  511  as viewed in the direction of the arrow XXb of  FIG. 20(   a ). Also,  FIG. 21(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  501  after pressing-in, and  FIG. 21(   b ) is a partially enlarged front view of the anti-vibration unit  501  after pressing-in. Further, in  FIG. 20(   b ), illustration of the anti-vibration base  13 , the outer tube member  12  and the like is omitted. 
         [0160]    As shown in  FIG. 20 , with respect to the extension section  511   c , the ridge line section (the corner) of the lower surface and the outer peripheral surface thereof is cut off linearly, and thereby an inclined surface  511   c   1  that inclines upward to the outer periphery side is formed continuously in the peripheral direction on the lower surface side (the lower side in  FIG. 20(   a )) of the extension section  511   c . That is, the inclined surface  511   c   1  is formed into an annular shape with the axis O at its center in the bottom view shown in  FIG. 20(   b ). As a result, the extension section  511   c  is formed into a trapezoidal shape in the front view (that is, as viewed in the direction orthogonal to the axis O). 
         [0161]    Therefore, in pressing in the extension section  511   c  to the press-fitting section  35 , the thickness dimension on the outer periphery side of the extension section  511   c  is made small, and the extension section  511   c  can be easily inserted to the extension section press-fitting space  36  of the press-fitting section  35 . 
         [0162]    Also, with the inclined surface  511   c   1  formed in the extension section  511   c , as shown in  FIG. 21(   b ), a space can be formed between the extension section  511   c  and the inner wall surface (the side surface and the lower surface) of the extension section press-fitting space  36  of the press-fitting section  35 . Therefore, the scraping chips generated in pressing in the extension section  511   c  to the press-fitting section  335  (the extension section press-fitting space  36 ) can be stored. Particularly, by forming the inclined surface  511   c   1  only on the lower surface side and having the formation region thereof as the required minimum, while the strength of the extension section  511   c  and the engagement area (that is, the engagement strength) with the inner wall surface of the extension section press-fitting space  36  are secured, the scraping chips having dropped on the bottom surface of the extension section press-fitting space  36  in pressing-in can be efficiently stored. 
         [0163]    Also, because the inclined surface  511   c   1  is formed continuously in the peripheral direction and the boss member  511  is formed into a symmetric shape around the axis O, it is not necessary to consider the orientation in the peripheral direction. Therefore, in arranging work in the vulcanizing mold at the time of vulcanizing molding and the press-in work of the anti-vibration device  510  to the first bracket  20  (the first bracket holding step; refer to  FIG. 2 ), the work for positioning in the peripheral direction can be omitted, and the man-hours during manufacturing can be reduced. 
         [0164]    Further, the formation position of the inclined surface  511   c   1  is not limited to the lower surface side (the lower side in  FIG. 20(   a )) of the extension section  511   c , and alternatively or additionally, it may be formed on the upper surface side (the upper side in  FIG. 20(   a )) of the extension section  511   c.    
         [0165]    Also, the application object of the present modification in which this inclined surface is formed is not limited to the extension section  511   c  of the boss member  511  in the fifth embodiment, and the inclined surface may also be arranged in the boss members  11 ,  711  in other embodiments. When the inclined surface is to be formed in the extension section  11   c  of the boss member  11 , it is preferable to form the surface not only on the right/left side (the right/left side in  FIG. 3(   a )) in the front view but also on the press-in direction side (the left side in  FIG. 6(   a )). Particularly, in the case of an aspect including the positioning wall  239 ,  339 , by forming the inclined surface on the press-in direction side of the extension section  11   c , the storage performance of the scraping chips generated in pressing-in can be improved, and the positional accuracy of the press-in position can be secured. 
         [0166]    Further, when the entire extension section  11   c  of the boss member  11  is covered by the rubber membrane  413   a  as the anti-vibration device  410  in the fourth embodiment, the rubber membrane  413   a  that becomes the excess margin in pressing-in can be stored in the space formed between the inclined surface of the extension section  11   c  and the inner wall surface of the extension section press-fitting space  36  by forming the inclined surface in the extension section  11   c . Therefore, the engagement strength between the boss member  11  and the press-fitting section  35  can be secured. 
         [0167]    In the third embodiment, although a case was described where the groove section  339   a  of a groove shape was formed in a part of the surface on the side facing the extension section press-fitting space  36  of the positioning wall  339 , the present invention is not necessarily limited to it, and other aspects are naturally possible. A first example of such other aspects will be described as a modification of the third embodiment referring to  FIG. 22  and  FIG. 23 . Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0168]      FIG. 22(   a ) is a partially enlarged cross-sectional view of the second bracket  330  in the modification, and  FIG. 22(   b ) is a partially enlarged rear view of the second bracket  330  as viewed from the direction of the arrow XXIIb of  FIG. 22(   a ). Also,  FIG. 23(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  301  after pressing-in, and  FIG. 23(   b ) is a partially enlarged front view of the anti-vibration unit  301  after pressing-in. 
         [0169]    As shown in  FIG. 22 , in the positioning wall  339  in the modification, a groove section  339   b  is recessively arranged in the entire surface facing the extension section press-fitting space  36 . That is, with respect to the positioning wall  339 , of the surface facing the extension section press-fitting space  36  and the shaft section press-fitting space  37  (the right side surface in  FIG. 22(   a )), only the surface facing the extension section press-fitting space  36  is recessively arranged, and this portion recessively arranged is made to be the groove section  339   b.    
         [0170]    Therefore, when the press-in section of the boss member  11  is pressed in to the press-fitting section  335  of the fixing member  331  as shown in  FIG. 23 , the shaft section  11   b  of the boss member  11  is made to abut upon the positioning wall  339 , and the press-in position thereof is positioned to the prescribed position. In this case, the scraping chips generated in pressing-in can be surely stored in the groove section  339   b , because the groove section  339   b  is recessively arranged in the entire surface facing the extension section press-fitting space  36 , and as a result, the positional accuracy of the press-in position of the boss member  11  can be secured. 
         [0171]    A second example in which the groove section  339   a  is another aspect will be described as a modification of the third embodiment referring to  FIG. 24  and  FIG. 25 . Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0172]      FIG. 24(   a ) is a partially enlarged cross-sectional view of the second bracket  330  in the modification, and FIG.  24 ( b ) is a partially enlarged rear view of the second bracket  330  as viewed from the direction of the arrow XXIVb of  FIG. 24(   a ). Also,  FIG. 25(   a ) is a partially enlarged cross-sectional view of the anti-vibration unit  301  after pressing-in, and  FIG. 25(   b ) is a partially enlarged front view of the anti-vibration unit  301  after pressing-in. 
         [0173]    As shown in  FIG. 24 , in a positioning wall  339   c  in the modification, the entire surface facing the extension section press-fitting space  36  is openingly formed. That is, the positioning wall  339   c  is formed into a rectangular parallelepiped shape that connects a pair of the restriction walls  38  with each other, and is formed only in a portion corresponding to the shaft section press-fitting space  37 . Therefore, with respect to the extension section press-fitting space  36 , both sides in the press-in direction (the start end side and the final end side) open to the side surfaces on both sides (the right side and the left side in  FIG. 24(   a )) of the fixing member  331 . 
         [0174]    Therefore, as shown in  FIG. 25 , when the press-in section of the boss member  11  is pressed in to the press-fitting section  335  of the fixing member  331 , the shaft section  11   b  of the boss member  11  is made to abut upon the positioning wall  339   c , and the press-in position thereof is positioned to a prescribed position. In this case, the positioning wall  339   c  is not formed in a portion corresponding to the extension section press-fitting space  36 , thus the scraping chips generated in pressing-in can be discharged to the outside, and it is possible to avoid catching the scraping chips between the extension section  11   c  and the positioning wall  339   c . As a result, the positional accuracy of the press-in position of the boss member  11  can be secured. 
         [0175]    In the eighth embodiment, although a case was described where, the press-in jig IJ was utilized in order to compress the anti-vibration device  810  in the axis 0 direction, the present invention is not necessarily limited to it, and it is naturally possible to employ other methods. An example of the other methods will be described as a modification of the eighth embodiment referring to  FIG. 26 . Also, with respect to the same portions as those of the respective embodiments described above, the same reference signs will be given, and description thereof will be omitted. 
         [0176]    From  FIG. 26(   a ) to  FIG. 26(   c ) are cross-sectional views showing the process of pressing-in of the anti-vibration unit  801  in the modification,  FIG. 26(   a ) corresponds to a state before pressing-in,  FIG. 26(   b ) corresponds to a state in the middle of pressing-in, and  FIG. 26(   c ) corresponds to a state after pressing-in respectively. 
         [0177]    As shown in  FIG. 26(   a ), in the bottom surface on the start end side in the press-in direction (the right side in  FIG. 26(   a )) of the extension section press-fitting space  36  of the second bracket  30  in the modification, an inclined surface  36   a  is formed which is inclined upward from the start end side of the press-in direction to the final end side (the left side in  FIG. 26(   a )). Also, with respect to the extension section press-fitting space  36 , the distance between opposing surfaces of an inner wall surface  36   b  of a region corresponding to the inclined surface  36   a  (the back side and the front side of the paper surface in  FIG. 26(   a )) is made equal to or slightly larger than the width dimension (the dimension in the direction vertical to the paper surface in  FIG. 26(   a )) of the extension section  11   c  of the boss member  11  pressed in. Therefore, the width dimension (the dimension in the direction vertical to the paper surface in  FIG. 26(   a )) of the inclined surface  36   a  is also made equal to or slightly larger than the width dimension of the extension section  11   c  of the boss member  11 . 
         [0178]    On the other hand, in the extension section  11   c  of the boss member  11  in the modification, an inclined surface  11   c   1  is formed in the lower surface on the press-in direction side (the left side in  FIG. 26(   a )). That is, the inclined surface  11   c   1  is formed by cutting off the ridge section (the corner) between the side surface on the press-in direction side and the lower surface of the extension section  11   c , and is inclined at an inclination angle equal to that of the inclined surface  36   a  of the extension section press-fitting space  36  in the press-in attitude (a state where the axis O is orthogonal to the press-in direction (the arrow A direction)). 
         [0179]    Also, the configuration of the press-in device used in pressing in the boss member  11  (the press-in section) of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  is similar to that of the case of the eighth embodiment. Therefore description thereof will be omitted. 
         [0180]    From the state shown in  FIG. 26(   a ), by movement of the first arm that holds the first bracket  20  and the second arm that holds the boss member  11  to the press-in direction (the arrow A direction), the inclined surface  11   c   1  in the extension section  11   c  of the boss member  11  is made to abut upon the inclined surface  36   a  in the extension section press-fitting space  36  of the press-fitting section  35 , and these first arm and second arm are further moved to the press-in direction. 
         [0181]    Thus, while the outer tube member  12  is moved horizontally to the press-in direction along with the first arm, the boss member  11  held by the second arm is guided on the inclined surface  36   a  of the extension section press-fitting space  36 , is thereby moved to the press-in direction while rising in the axis O direction along with the second arm along the inclined surface  36   a  (that is, while compressively deforming the anti-vibration device  810  in the axis O direction), and is pressed in to the press-fitting section  35  in the fixing member  31  of the second bracket  30  upon going beyond the final end of the inclined surface  36   a.    
         [0182]    Therefore, in the present modification also, similarly to the case of the eighth embodiment, the step of pressing in the boss member  11  of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  for fixing and the step of compressing the anti-vibration device  810  in the axis O direction can be effected simultaneously, and the man-hours during manufacturing can be reduced. Also, the structure of the press-in device can be simplified, and the facility cost for pressing in the boss member  11  of the anti-vibration device  810  to the fixing member  31  (the press-fitting section  35 ) of the second bracket  30  can be reduced. Further, in the present modification, the press-in jig IJ is not required, and the facility cost can be reduced correspondingly. 
         [0183]    In the first to sixth embodiments and the eighth embodiment, although a case was described where the cross-sectional shape of the extension section press-fitting space  36  was constant along the press-in direction, the present invention is not necessarily limited to it, and the cross-sectional shape of the extension section press-fitting space  36  may be made into a cross-sectional shape equal to or slightly larger than that of the extension section  11   c  at least in a part on the start end side in the press-in direction. Thus, generation of the scraping chips can be suppressed. 
         [0184]    In the first to sixth embodiments and the eighth embodiment, although a case was described where the cross-sectional shape (the shape as viewed in the press-in direction) of the extension section press-fitting space  36  was made similar to the cross-sectional shape (the shape as viewed in the press-in direction) of the extension section  11   c ,  511   c  (that is, a case where all surfaces of the upper surface, bottom surface and side surface of the inner wall surfaces of the extension section press-fitting space  36  have the press-in allowance), the present invention is not necessarily limited to it. For example, only the upper surface and the bottom surface of the extension section press-fitting space  36  may have the press-in allowance, or only the side surface of the extension section press-fitting space  36  may have the press-in allowance. 
         [0185]    The configuration of some or all of the respective embodiments or modifications described above may be combined with or may be replaced by the configuration of the other embodiments or the modifications. For example, an aspect is exemplified in which the groove section  339   a  in the third embodiment is added to the surface that faces the extension section press-fitting space  36  of the positioning wall  639  in the sixth embodiment. 
       REFERENCE SINGS LIST 
       [0186]