Patent Publication Number: US-9903437-B2

Title: Vibration absorption device

Description:
TECHNICAL FIELD 
     The present invention relates to a vibration absorption device that is to be used as an engine mount for general industrial machinery or an automobile or the like and that absorbs and damps vibrations transmitted from a vibration generating portion such as an engine or the like to a vibration receiving portion such as a vehicle body or the like. 
     BACKGROUND ART 
     A vibration absorption device that serves as an engine mount is provided between, for example, an engine of a vehicle that acts as a vibration generating portion and a vehicle body that acts as a vibration receiving portion. The vibration absorption device absorbs vibrations produced by the engine and suppresses transmission of the vibrations to the vehicle body side. A sealed fluid-type vibration absorption device is known as this kind of vibration device. In a sealed fluid-type vibration absorption device, an elastic body and a pair of liquid chambers are provided inside the device, and the pair of chambers are in fluid communication with one another through a restriction channel. According to this sealed fluid-type vibration absorption device, when an engine mounted thereon operates and produces vibrations, the vibrations are absorbed by a damping function of the elastic body, viscous resistance of a liquid in an orifice communicating between the pair of chambers and suchlike, and transmission of the vibrations to the vehicle body side is suppressed. 
     Sealed fluid-type vibration absorption devices as described above include, for example, those illustrated in Patent References 1 to 5. In each of the vibration absorption devices recited in Patent References 1 to 5, a liquid chamber is divided by a dividing member into a primary chamber and a secondary chamber, and the primary chamber and the secondary chamber are put into fluid communication by a restriction channel structured at an outer periphery of the dividing member. 
     Now, if the restriction channel is structured at an outer side of the dividing member, between the dividing member and a restriction channel member that is a separate member from the dividing member, a diaphragm may be adhered directly to the restriction channel member by vulcanization or the like. In such a case, assurance of sealing between the dividing member and the restriction channel member and diaphragm is required.
     Patent Reference 1: Japanese Patent Application Laid-Open (JP-A) No. 2006-90388   Patent Reference 2: JP-A No. 2004-204964   Patent Reference 3: JP-A No. 2005-221080   Patent Reference 4: JP-A No. H8-14317   Patent Reference 5: JP-A No. 2004-3634   

     DISCLOSURE OF INVENTION 
     Technical Problem 
     The present invention has been made in consideration of the situation described above, and an object of the present invention is to provide a vibration absorption device capable of assuring sealing between a dividing member and a restriction channel member and diaphragm. 
     Solution to Problem 
     In order to achieve the object described above, a vibration absorption device relating to a first aspect of the invention includes: a first mounting member that is coupled to one of a vibration generating portion or a vibration receiving portion; a second mounting member that is tubular and is coupled to the other of the vibration generating portion or the vibration receiving portion; an elastic body that is disposed between the first mounting member and the second mounting member and is coupled to both the mounting members; a primary chamber constituted at an inner side of the second mounting member, the elastic body serving as a portion of a dividing wall of the primary chamber, and liquid being sealed in the primary chamber; a secondary chamber in which liquid is sealed, at least a portion of a dividing wall of the secondary chamber being formed by a diaphragm, and the secondary chamber being capable of expanding and contracting; a dividing member that divides the primary chamber from the secondary chamber, the dividing member including a tubular tube portion, a flange portion that is structured to extend to a radial direction outer side from the primary chamber side end of the tube portion, an outer periphery of the flange portion being disposed along an inner periphery of the second mounting member, and a movable elastic film that is disposed at the radial direction inner side of the tube portion; and a restriction channel member that is an annular body separate from the dividing member, that is disposed between the tube portion of the dividing member and the second mounting member, that includes a channel outer tube portion disposed along an inner periphery of the second mounting member and a floor portion formed continuously from the channel outer tube proportion, disposed opposing the flange portion, and disposed within the tube portion in a tube axial direction, and that structures a restriction channel between the dividing member and the restriction channel member, the restriction channel causing fluid communication between the primary chamber and the secondary chamber, and an outer periphery end of the diaphragm being adhered to at least an inner periphery of the floor portion. 
     In a vibration absorption device with the structure described above, the restriction channel member is a separate body from the dividing member, and the restriction channel that communicates between the primary chamber and the secondary chamber is formed between the dividing member and the restriction channel member. At least the outer periphery end of the diaphragm structuring the secondary chamber is adhered to the inner periphery of the floor portion, and the restriction channel is put into fluid communication with the secondary chamber via the aperture formed in the floor portion of the restriction channel member. The floor portion of the restriction channel member is disposed within the tube portion in the tube axial direction. Thus, by the restriction channel member to which the outer periphery end of the diaphragm is adhered being crimped to the radial direction inner side, sealing may be reliably implemented between the inner periphery side of the floor portion and the tube portion outer periphery of the dividing member. 
     A vibration absorption device relating to a second aspect of the invention is further provided with a channel inner tube portion that is formed continuously from the floor portion and is disposed along an outer periphery of the tube portion. 
     According to the above structure, sealing with the tube portion outer face of the dividing member may be implemented using the inner side face of the channel inner tube portion. 
     In a vibration absorption device relating to a third aspect of the invention, the channel inner tube portion is extended toward the secondary chamber side from an inner end portion of the floor portion. 
     According to the above structure, sealing with the tube portion may be reliably implemented by crimping the channel inner tube portion to the radial direction inner side. 
     In a vibration absorption device relating to a fourth aspect of the invention, an aperture in fluid communication with the secondary chamber is formed in a circumferential direction portion of the floor portion and, at a position corresponding with the aperture, the diaphragm is adhered to the restriction channel member at the radial direction outer side relative to the aperture. 
     As described above, the aperture may be formed in the floor portion of the restriction channel member and cause fluid communication between the restriction channel and the secondary chamber. 
     In a vibration absorption device relating to a fifth aspect of the invention, the diaphragm structures the secondary chamber at the radial direction inner side relative to the inner periphery end of the floor portion, and the diaphragm is protruded to the radial direction outer side at a fluid communication position corresponding with the aperture in the floor portion. 
     According to the above structure, the outer periphery of the secondary chamber is formed at the radial direction inner side of the floor portion. Thus, a secondary chamber region may be structured to be compact in the radial direction. 
     In a vibration absorption device relating to a sixth aspect of the invention, the diaphragm is structured with a greater thickness at the fluid communication position than at other portions of the diaphragm that structure the secondary chamber. 
     According to the above structure, deformation of the diaphragm at the fluid communication position by flows of the liquid may be suppressed. 
     In a vibration absorption device relating to a seventh aspect of the invention, a retracted portion that is retracted to the radial direction inner side is structured at a circumferential direction portion of the tube portion of the dividing member, and the restriction channel and the secondary chamber are in fluid communication via an aperture portion that is opened from the restriction channel toward an outer face of the retracted portion. 
     As described above, the restriction channel and the secondary chamber may be put into fluid communication by the retracted portion being formed in the dividing member. 
     Advantageous Effects of Invention 
     According to the present invention as described hereabove, sealing between the dividing member and the restriction channel member and diaphragm may be assured. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side sectional diagram illustrating structure of a vibration absorption device relating to a first exemplary embodiment of the present invention. 
         FIG. 2  is a perspective diagram illustrating structure of a dividing member, restriction channel member and diaphragm of the vibration absorption device relating to the first exemplary embodiment of the present invention. 
         FIG. 3  is a perspective diagram illustrating structure of the restriction channel member of the vibration absorption device relating to the first exemplary embodiment of the present invention. 
         FIG. 4  is a partial sectional diagram illustrating a variant example of the restriction channel member of the vibration absorption device relating to the first exemplary embodiment of the present invention. 
         FIG. 5  is a partial sectional diagram illustrating another variant example of the restriction channel member of the vibration absorption device relating to the first exemplary embodiment of the present invention. 
         FIG. 6A  is a partial sectional diagram illustrating the other variant example of the restriction channel member of the vibration absorption device relating to the first exemplary embodiment of the present invention (before assembly). 
         FIG. 6B  is a partial sectional diagram illustrating the other variant example of the restriction channel member of the vibration absorption device relating to the first exemplary embodiment of the present invention (after assembly). 
         FIG. 7  is a side sectional diagram illustrating structure of a vibration absorption device relating to a second exemplary embodiment of the present invention. 
         FIG. 8  is a perspective diagram illustrating structure of a dividing member of the vibration absorption device relating to the second exemplary embodiment of the present invention. 
         FIG. 9  is a plan view illustrating structure of the dividing member of the vibration absorption device relating to the second exemplary embodiment of the present invention. 
         FIG. 10  is a perspective diagram illustrating structure of a restriction channel member of the vibration absorption device relating to the second exemplary embodiment of the present invention. 
         FIG. 11  is a perspective diagram illustrating structure of the restriction channel member and a diaphragm of the vibration absorption device relating to the second exemplary embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     First Exemplary Embodiment 
     Herebelow, a vibration absorption device relating to a first exemplary embodiment of the present invention is described with reference to the attached drawings. 
     A vibration absorption device  10  relating to the exemplary embodiment of the present invention is illustrated in  FIG. 1 . This vibration absorption device  10  is employed in an automobile as an engine mount that supports an engine, which is a vibration generating portion, at a vehicle body, which is a vibration receiving portion. The label S in the drawings indicates a central axis, a direction along this central axis is an axial direction S of the device, and descriptions are given hereinafter with an up-down direction in the drawings being an up-down direction of the vibration absorption device  10 . Vibrations (primary vibrations), the absorption of which is a principal objective, are inputted in the axial direction S. 
     As illustrated in  FIG. 1 , the vibration absorption device  10  is provided with a first mounting member  14  and a second mounting member  12 . 
     The second mounting member  12  is in a substantially circular tube shape, and a step portion  12 B is formed at an intermediate portion thereof. Sandwiching the step portion  12 B, the upper side of the second mounting member  12  serves as an elastic body coupling portion  12 A, and the lower side serves as a division nipping portion  12 C with a smaller diameter than the elastic body coupling portion  12 A. A crimping portion  12 D that is crimped to the radial direction inner side is formed at a lower end portion of the division nipping portion  12 C. The second mounting member  12  is coupled to the vehicle body via an unillustrated bracket. 
     The first mounting member  14  is in a substantially circular rod shape with a smaller diameter than the second mounting member  12 . A threaded hole  14 A, in which a female thread is formed, is formed toward the axial direction lower side from a central region of an upper face of the first mounting member  14 . An unillustrated bolt that is coupled to the engine side is threaded into the threaded hole  14 A. 
     A lower portion of the first mounting member  14  is disposed at the inner side of the second mounting member  12  so as to be coaxial with the second mounting member  12 . The central axes of the first mounting member  14  and the second mounting member  12  are on the axial direction S of the vibration absorption device  10 . 
     An elastic body  16  made of rubber, which serves as a vibration-absorbing main body, is disposed between the first mounting member  14  and the second mounting member  12 . The elastic body  16  is adhered by vulcanization to the outer face of the first mounting member  14  and is adhered by vulcanization to the elastic body coupling portion  12 A and step portion  12 B of the second mounting member  12 . Thus, the first mounting member  14  and the second mounting member  12  are elastically coupled. 
     A cover portion  18  in the form of a thin film is integrally formed at the elastic body  16 , protruding downward from a lower end portion thereof. The cover portion  18  is adhered by vulcanization to the inner periphery face of the division nipping portion  12 C of the second mounting member  12 , and covers the inner wall of the second mounting member  12 . A step portion  12 E is formed at the lower side of a portion of the cover portion  18  that corresponds with the step portion  12 B. A flange portion  24  of a dividing member  20 , which is described below, is abutted against this step portion  12 E. 
     The dividing member  20  and a restriction channel member  30  are disposed at the inner periphery side of the cover portion  18 . The dividing member  20  and the restriction channel member  30  are fixed by the division nipping portion  12 C and the lower end portion  12 D being crimped to the radial direction inner side. As illustrated in  FIG. 2 , the dividing member  20  is formed in a hat shape, provided with a tube portion  22 , the flange portion  24  and a movable elastic film  28 . 
     The tube portion  22  has a circular tube shape, and the flange portion  24  is structured to extend to the radial direction outer side from an upper end portion of the tube portion  22 . An outer periphery end of the flange portion  24  abuts against the step portion  12 E, and is thus positioned in the axial direction S. A fluid communication hole  24 A that communicates between a primary chamber  40 , which is described below, and a restriction channel  26  is formed in the flange portion  24 . A curved portion  22 R that is inflected to the radial direction inner side is formed at a lower end portion of the tube portion  22 . 
     The movable elastic film  28  is disposed at the radial direction inner side of the tube portion  22 . The movable elastic film  28  is in a circular plate shape and is elastically deformable. The movable elastic film  28  is adhered to the inner wall of the tube portion  22  so as to divide the interior of the tube portion  22  between above and below. The movable elastic film  28  is structured by an elastically deformable film of a rubber, a resin or the like. 
     The primary chamber  40  is constituted at the inner side, enclosed by a lower face of the elastic body  16  and an upper face of the dividing member  20 . A liquid is sealed in the primary chamber  40 . Water, oil, ethylene glycol or the like may be used as the liquid. 
     As illustrated in  FIG. 2  and  FIG. 3 , the restriction channel member  30  is formed as a separate member from the dividing member  20 . The restriction channel member  30  has an annular shape, and is provided with a channel outer tube portion  32 , a floor portion  34  and a channel inner tube portion  36 . 
     The channel outer tube portion  32  has a circular tube shape whose outer diameter is a little smaller than the division nipping portion  12 C, and is disposed at the inner periphery side of the division nipping portion  12 C. As illustrated in  FIG. 1 , the channel outer tube portion  32  is disposed apart from and opposing the outer periphery face of the tube portion  22  of the dividing member  20 , and is pressed against the inner periphery face of the division nipping portion  12 C with the cover portion  18  therebetween. 
     The floor portion  34  is formed to be inflected to the radial direction inner side from a lower end portion of the channel outer tube portion  32 , and is disposed apart from and opposing the flange portion  24  at the outer periphery side of the tube portion  22  of the dividing member  20 . The floor portion  34  is disposed within the tube portion  22  in the axial direction S, that is, so as to overlap with the tube portion  22  when viewed from a radial direction. 
     The channel inner tube portion  36  is formed to be inflected to the downward direction from an inner periphery portion of the floor portion  34 , and is disposed along the tube portion  22  of the dividing member  20 . A lower end portion of the channel inner tube portion  36  protrudes further downward than a lower end portion of the second mounting member  12 . 
     The restriction channel  26 , which communicates between the primary chamber  40  and a secondary chamber  42 , which is described below, is constituted to be enclosed by the inner periphery face of the channel outer tube portion  32 , the upper face of the floor portion  34 , the lower face of the flange portion  24  and the outer periphery face of the tube portion  22 . 
     As illustrated in  FIG. 3 , a fluid communication aperture  30 A is formed in the restriction channel member  30  at a portion of the circumferential direction thereof. The fluid communication aperture  30 A is formed by a circumferential direction portion of the channel inner tube portion  36  and a circumferential direction portion of the floor portion  34  being cut away. At the region at which the floor portion  34  is cut away, a reinforcement portion  34 A is retained at the radial direction outer side for crimping. 
     A diaphragm  50  in the form of an elastic film is adhered by vulcanization to the restriction channel member  30  so as to cover a lower side opening thereof. A seal portion  56  is vulcanization-formed integrally with the diaphragm  50  so as to cover the radial direction inner side of the floor portion  34  and the inner periphery face of the channel inner tube portion  36  of the restriction channel member  30 . An outer periphery of the diaphragm  50  is adhered to the restriction channel member  30  by the seal portion  56 . An inner film portion  58  is formed integrally with the seal portion  56  and covers the inner side of the floor portion  34  and the inner side of the channel outer tube portion  32 . 
     The diaphragm  50  is provided with a tube wall portion  52  and a movable floor portion  54 . The tube wall portion  52  has a substantially circular tube shape, an upper portion end of which serves as the seal portion  56  and is adhered to the inner periphery side of the floor portion  34  of the restriction channel member  30 . A region of the tube wall portion  52  that corresponds with the fluid communication aperture  30 A has the form of a protrusion to the radial direction outer side, and is adhered to the outer periphery side of the floor portion  34 . Thus, a fluid communication channel  50 R that communicates with the below-described secondary chamber  42  is structured between the outer periphery of the tube portion  22  and the diaphragm  50 . 
     The movable floor portion  54  has a bowl shape, an outer periphery of which is continuous with the tube wall portion  52 , and is formed such that a floor portion of the bowl is oriented to the upper side in a state in which no vibration is being inputted. The movable floor portion  54  is structured integrally with the tube wall portion  52 . 
     The secondary chamber  42  is constituted at the inner side, enclosed by the diaphragm  50  and the lower face of the dividing member  20 . The secondary chamber  42  is in fluid communication with the primary chamber  40  via the fluid communication aperture  30 A, the restriction channel  26  and the fluid communication hole  24 A. The diaphragm  50  is structured with a greater thickness where it is in the shape of a protrusion below the communication aperture  30 A than at other portions. Hereinafter, the corresponding portion of the diaphragm  50  is referred to as a fluid communication protrusion portion  50 A. Similarly to the primary chamber  40 , the liquid is sealed in the secondary chamber  42 . Because the fluid communication protrusion portion  50 A is made thicker than other portions of the diaphragm  50 , movements of the fluid communication protrusion portion  50 A when the secondary chamber  42  is expanding and contracting are suppressed, and the sealed liquid may pass through the fluid communication channel  50 R smoothly. 
     The dividing member  20  is pushed into a cavity portion of the restriction channel member  30 , with the seal portion  56  therebetween, such that the opposite side of the dividing member  20  from the side at which the flange portion  24  is provided, that is, the curved portion  22 R, is to the diaphragm  50  side, and such that the fluid communication aperture  30 A and the fluid communication hole  24 A do not overlap in the circumferential direction but are offset. The tube portion  22  of the dividing member  20  and the channel inner tube portion  36  of the restriction channel member  30  are tightly contacted by the seal portion  56 . 
     A barrier wall  59  is formed, integrally with the seal portion  56  and the inner film portion  58 , between the fluid communication aperture  30 A and the fluid communication hole  24 A in the circumferential direction. Thus, the fluid communication hole  24 A side and the fluid communication aperture  30 A side of the restriction channel  26  are partitioned by the barrier wall  59 . 
     Next, assembly of the vibration absorption device  10  relating to the present exemplary embodiment is described. 
     First, in an unillustrated mold, the elastic body  16  is adhered by vulcanization between the first mounting member  14  and the second mounting member  12 , and the cover portion  18  is formed. Separately, using a mold, the diaphragm  50 , the seal portion  56  and the inner film portion  58  are vulcanization-formed at the restriction channel member  30 . In addition, the movable elastic film  28  is vulcanization-formed at the dividing member  20 . 
     Then, assembly of the dividing member  20  with the restriction channel member  30  is implemented by pushing the dividing member  20 , from the opposite side thereof from the side at which the flange portion  24  is provided, into the side of the restriction channel member  30  at which the diaphragm  50  is not formed and tightly contacting the outer periphery of the tube portion  22  and the lower face of the flange portion  24  with the inner periphery and the upper end face of the restriction channel member  30 . At this time, the barrier wall  59  is disposed between the fluid communication aperture  30 A of the restriction channel member  30  and the fluid communication hole  24 A of the dividing member  20 . 
     Then, the set of the first mounting member  14 , the second mounting member  12  and the elastic body  16  and the set of the dividing member  20 , the restriction channel member  30  and the diaphragm  50  that have been integrated as described above are assembled within the liquid that is to be sealed thereinside. In this assembly, the dividing member  20  and restriction channel member  30  are inserted from the lower side of the second mounting member  12 , the outer periphery of the flange portion  24  of the dividing member  20  is engaged with the step portion  12 E, and an upper end face of the channel outer tube portion  32  of the restriction channel member  30  is abutted against the lower face of the flange portion  24 . Then, the crimping portion  12 C and lower end portion  12 D of the second mounting member  12  are crimped to the radial direction inner side. Thus, the vibration absorption device  10  may be assembled. 
     Next, operation of the vibration absorption device  10  relating to the present exemplary embodiment configured as described above is described. 
     In the vibration absorption device  10 , when a vibration is inputted from the engine or vehicle body side, the elastic body  16  that is the vibration-absorbing main body is elastically deformed by the vibration, and the vibration is damped and absorbed by the elastic body  16 . 
     In the vibration absorption device  10 , the internal volume of the primary chamber  40  is expanded and contracted by the deformation of the elastic body  16 , and the liquid reciprocatingly flows through the restriction channel  26  between the primary chamber  40  and the secondary chamber  42  in association with the expansions and contractions of the primary chamber  40 . At this time, if a vibration in a relatively low frequency region, for example, a shake vibration or the like, is being inputted, liquid column resonance occurs, in which the liquid flows in and out between the primary chamber  40  and the secondary chamber  42  in resonance with the input vibration. In this case, the vibration energy is absorbed by pressure changes in the liquid that occur in the cavity in the restriction channel  26 , viscous resistance of the liquid flows, and the like. Thus, in the vibration absorption device  10 , particularly vibrations in a relatively low frequency region such as shake vibrations and the like may be effectively absorbed by liquid column resonance between the primary chamber  40  and the secondary chamber  42 . 
     The diaphragm  50  suppresses a rise in liquid pressure inside the secondary chamber  42  by elastically deforming so as to expand to the outer side when liquid from the primary chamber  40  is inputted into the secondary chamber  42 . Thus, restriction of an inflow of the liquid from inside the primary chamber  40  to inside the secondary chamber  42  due to a rise in the liquid pressure in the secondary chamber  42  may be prevented. 
     Alternatively, if a vibration in a relatively high frequency region is inputted from the engine, for example, an idling vibration or the like, clogging occurs in the restriction channel  26  and the vibrations may not be absorbed by liquid column resonance. At this time, the movable elastic film  28  is elastically deformed by the vibrations in the high frequency region that are transmitted to the liquid inside the primary chamber  40  so as to expand and contract the volume inside the primary chamber  40 . Thus, because a rise in liquid pressure in the primary chamber  40  is suppressed, even when vibrations in a relatively high frequency range are inputted from the engine, a rise in the dynamic spring coefficient in association with a rise in liquid pressure of the liquid in the primary chamber  40  may be suppressed, and vibrations in the high frequency region too may be effectively absorbed. 
     In the present exemplary embodiment, because the restriction channel member  30  and the dividing member  20  are formed as separate members, the diaphragm  50  may be molded integrally with the restriction channel member  30 . In the present exemplary embodiment, the diaphragm  50  is formed by vulcanization-molding of a rubber material. However, for example, the restriction channel member  30  may be formed of a resin such as polypropylene (PP) or the like, the diaphragm  50  may be formed of a thermoplastic vulcanizate (a crosslinked elastomer), and the two may be integrally structured by twin-molding. 
     In the present exemplary embodiment, because the floor portion  34  of the restriction channel member  30  is disposed within the tube portion  22  in the axial direction S, sealing between the inner side of the floor portion  34  and the outer periphery of the tube portion  22  by the seal portion  56  may be reliably implemented by the division nipping portion  12 C of the second mounting member  12  being crimped to the radial direction inner side. 
     In the present exemplary embodiment, because the fluid communication channel  50 R is constituted at the radial direction outer side of the dividing member  20 , the dividing member  20  may be formed in a circular tube shape, the movable elastic film  28  may be formed in a circular plate shape, and a larger area may be assured. 
     In the present exemplary embodiment, because the outer radius of the diaphragm  50  is adhered to the inner periphery side of the restriction channel member  30  and only the portion corresponding with the fluid communication aperture  30 A is formed as a protrusion to the radial direction outer side, the lower portion of the vibration absorption device  10  may have a small diameter and be made compact. 
     In the present exemplary embodiment, because the fluid communication protrusion portion  50 A of the diaphragm  50  is made thicker than other portions of the diaphragm  50 , movements of the fluid communication protrusion portion  50 A when the secondary chamber  42  is expanding and contracting may be suppressed, and the sealed liquid may pass through the fluid communication channel  50 R smoothly. 
     In the present exemplary embodiment, the restriction channel member  30  includes the channel inner tube portion  36 . However, as illustrated in  FIG. 4 , a restriction channel member  30 - 2  that is formed without the channel inner tube portion  36  may be formed. 
     Further, as illustrated in  FIG. 5 , a restriction channel member  30 - 3  in which the channel inner tube portion  36  of the restriction channel member  30  is inflected to the upper side may be formed. 
     Moreover, when the channel inner tube portion  36  is included as in the present exemplary embodiment, contact of the restriction channel member  30  with the outer face of the tube portion  22 , via the seal portion  56 , is area contact, and damage to the seal portion  56  by the crimping process or the like may be suppressed. 
     Further still, when the channel inner tube portion  36  has the structure that is inflected to the lower side as in the present exemplary embodiment, the channel inner tube portion  36  may be retained by a robot arm during assembly, and the seal portion  56  and the tube portion  22  may be more reliably sealed together. 
     In the present exemplary embodiment, because the curved portion  22 R is formed at the distal end of the tube portion  22  of the dividing member  20 , when the restriction channel member  30  and the dividing member  20  are assembled, push-in performance (assembly performance) of the dividing member  20  is excellent. Further, shifting of rubber volume of the seal portion  56  may be implemented smoothly by the curved portion  22 R, and sealing between the dividing member  20  and the seal portion  56  is improved. Further yet, because the curved portion  22 R is formed, damage to the rubber by a distal end edge of the tube portion  22  may be avoided. 
     As illustrated in  FIG. 6A , the seal portion  56  may have a shape in which a step portion  56 D is provided at the inner side of the channel inner tube portion  36 . At the step portion  56 D, the diaphragm  50  side of the seal portion  56  is thicker. When this step portion  56 D is provided, sealing between the lower end of the seal portion  56  and the vicinity of the curved portion  22 R when assembly has been carried out as illustrated in  FIG. 6B  may be improved. 
     Second Exemplary Embodiment 
     Herebelow, a vibration absorption device relating to a second exemplary embodiment of the present invention is described with reference to the drawings. In the present exemplary embodiment, portions that are the same as in the first exemplary embodiment are assigned the same reference numerals and detailed descriptions thereof are not given. 
     As illustrated in  FIG. 7 , a vibration absorption device  60  of the second exemplary embodiment is provided with the second mounting member  12 , the first mounting member  14  and the elastic body  16 . These members have the same structures as in the first exemplary embodiment. 
     As illustrated in  FIG. 8 , a dividing member  70  is formed in a hat shape, provided with a tube portion  72 , a flange portion  74  and a dividing portion  76 . 
     The tube portion  72  has a tube shape. As illustrated in  FIG. 9 , a retracted portion  72 A that is withdrawn to the radial direction inner side is formed at a portion of the circumferential direction of the tube portion  72 . The retracted portion  72 A is formed to be retracted toward the radial direction inner side, and a retraction cavity  72 R is formed between the retracted portion  72 A and the restriction channel member  62 . A fluid communication hole  72 H is formed in the tube portion  72  at a different position from the retracted portion  72 A. 
     The flange portion  74  is structured to extend to the radial direction outer side from one end of the tube portion  72  and is formed in a flange shape. The dividing portion  76  is structured to extend to the radial direction inner side from the other end of the tube portion  72 . The dividing portion  76  is provided with a frame portion  77 , which is an outer periphery portion of the dividing portion  76  and is structured integrally with the tube portion  72 , and a movable elastic film  78 , which is provided at the radial direction inner side of the tube portion  72 . A portion of the movable elastic film  78  that meets up with the retracted portion  72 A is linear, and the rest of the outer periphery of the movable elastic film  78  has a circular arc shape. The movable elastic film  78  is structured by a film that is elastically deformable, of a rubber, a resin or the like. 
     A restriction channel member  62  of the present exemplary embodiment too is a separate body from the dividing member  70 . The restriction channel member  62  has an annular shape, and a cross-section thereof is in a letter J shape whose opening portion is oriented to the upper side in the axial direction S. That is, the restriction channel member  62  includes the channel outer tube portion  32  disposed along the inner periphery of the division nipping portion  12 C, the floor portion  34  that is formed to be continuous from the channel outer tube portion  32  and disposed to oppose the flange portion  24 , and a channel inner tube portion  62 A that is formed to be continuous from the floor portion  34 , is inflected upward, is formed to be shorter in the axial direction than the channel outer tube portion  32 , and is disposed along the outer periphery of the tube portion  22 . 
     The outer diameter of the restriction channel member  62  and the outer diameter of the flange portion  74  of the dividing member  70  are substantially the same, and these outer diameters are smaller than the diameter of the division nipping portion  12 C of the second mounting member  12 . The inner diameter of the restriction channel member  62  is larger than the outer diameter of the tube portion  22 . The tube portion  72  of the dividing member  70  is inserted into a cavity portion of the restriction channel member  62 . 
     The diaphragm  50  is adhered by vulcanization to the restriction channel member  62  so as to cover the opening at the floor portion  34  side of the restriction channel member  62 . As illustrated in  FIG. 7 , the seal portion  56  is vulcanization-formed integrally with the diaphragm  50  at the restriction channel member  62  so as to cover the radial direction inner side of the channel inner tube portion  62 A. The inner film portion  58  is vulcanization-formed integrally with the diaphragm  50  so as to fill a region enclosed by the channel inner tube portion  62 A, the floor portion  34  and the channel outer tube portion  32  and to cover the upper end of the channel outer tube portion  32  from the inner periphery face thereof. 
     The dividing member  70  is pushed into the cavity portion of the restriction channel member  62 , with the seal portion  56  therebetween, such that the dividing portion  76  is to the diaphragm  50  side. The tube portion  72  of the dividing member  70  and the channel inner tube portion  62 A of the restriction channel member  62  are tightly contacted by the seal portion  56 . As illustrated in  FIG. 11 , a barrier wall  67  is formed integrally with the seal portion  56  and the inner film portion  58  at a region corresponding with the fluid communication hole  72 H. Thus, the fluid communication hole  72 H side and an aperture  68  side of a restriction channel  80 , which is described below, are partitioned by the barrier wall  67 . 
     In a state in which the outer periphery end of the flange portion  74  of the dividing member  70  is engaged with the step portion  12 E, the dividing member  70  and the restriction channel member  62  are fitted in at the inner side of the division nipping portion  12 C of the second mounting member  12 . The crimping portion  12 D of the division nipping portion  12 C is crimped to the radial direction inner side. Thus, the channel outer tube portion  32  of the restriction channel member  62  is tightly contacted with the cover portion  18  and the seal portion  56  is tightly contacted with the tube portion  72 . 
     The restriction channel  80  is constituted in a region enclosed by the inner sides of the J shape of the restriction channel member  62 , the tube portion  72  of the dividing member  70 , and the flange portion  74 . The restriction channel  80  is put into fluid communication with the primary chamber  40  by the fluid communication hole  72 H. The restriction channel  80  is also put into fluid communication with the secondary chamber  42  by the aperture  68 . Thus, the primary chamber  40  and the secondary chamber  42  are in fluid communication via the restriction channel  80 . 
     As illustrated in  FIG. 7 , the aperture  68  is formed at a position corresponding with the retracted portion  72 A of the tube portion  72 , and is opened to the radial direction inner side, toward the retracted portion  72 A. Thus, the aperture  68  is disposed at the primary chamber  40  side relative to the dividing portion  76  of the dividing member  70 , and the aperture  68  is in fluid communication with the secondary chamber  42  via the retraction cavity  72 R. 
     Assembly and operation of the vibration absorption device  60  of the present exemplary embodiment are the same as in the first exemplary embodiment. 
     In the vibration absorption device  60  of the present exemplary embodiment, the same effects may be provided as in the first exemplary embodiment. The structures and variant examples recited in the first exemplary embodiment may be used with the restriction channel member  62 .