Patent Publication Number: US-2023151835-A1

Title: Connection Structure

Description:
CLAIM OF PRIORITY 
     This application is a Continuation of International Application No. PCT/JP2021/027313 filed on Jul. 21, 2021, which claims benefit of Japanese Patent Application No. 2020-153251 filed on Sep. 11, 2020. The entire contents of each application noted above are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connection structure. 
     2. Description of the Related Art 
     A connection structure of a vibration member via a vibration isolation member has been developed in which the vibration isolation member includes a tubular portion extending in a vertical direction and an inner ward portion disposed inside the tubular portion and having a through-hole penetrating in the vertical direction, and a beam portion that connects the tubular portion to the inner ward portion. The upper end of the tubular portion is located above the upper end of the inner ward portion, and the lower end of the tubular portion is located below the lower end of the inner ward portion. The outer periphery of the tubular portion of the vibration isolation member has a groove circumferentially formed thereon at a middle position in the vertical direction (refer to, for example, Japanese Unexamined Patent 
     SUMMARY OF THE INVENTION 
     Since the outer periphery of the tubular portion of an existing vibration isolation member has a groove circumferentially formed thereon at a middle position in the vertical direction, it is difficult to easily manufacture vibration isolation members by using a mold of a vertical pull-out type. 
     Accordingly, the present invention provides a connection structure that can be easily manufactured. 
     According to an embodiment of the present invention, a connection structure includes first and second members disposed facing each other in a relatively movable manner and a damper member, where the first and second members are connected with each other via the damper member. The damper member is made of an elastically deformable material, and the damper member includes a cylindrical portion having a through-hole that penetrates in an axial direction of the cylindrical portion, a flange portion provided on an outer periphery of the cylindrical portion so as to extend radially outward, a first vibration absorbing portion provided on an inner periphery and the outer periphery of the cylindrical portion, and a second vibration absorbing portion provided on one of a first contact surface and a second contact surface of the flange portion. The first member includes a convex support portion fitting to an inner periphery of the cylindrical portion and a first contact portion in contact with the first contact surface of the flange portion, and the second member includes a concave support portion fitting to the outer periphery of the cylindrical portion and a second contact portion in contact with a second contact surface opposite the first contact surface of the flange portion. The first vibration absorbing portion is a plurality of ribs each protruding radially outward of the cylindrical portion and extending in the axial direction of the cylindrical portion, and the plurality of ribs are provided alternately on the inner periphery and outer periphery of the cylindrical portion such that the positions of the ribs differ from one another in a circumferential direction of the cylindrical portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates the cross-sectional structure of a connection structure according to an embodiment; 
         FIG.  2 A  illustrates a first member; 
         FIG.  2 B  illustrates the first member; 
         FIG.  3 A  illustrates a second member; 
         FIG.  3 B  illustrates the second member; 
         FIG.  4 A  illustrates a damper member; 
         FIG.  4 B  illustrates the damper member; 
         FIG.  5 A  illustrates the damper member; 
         FIG.  5 B  illustrates the damper member; 
         FIG.  6    illustrates the damper member; and 
         FIG.  7    illustrates a screw. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments to which a connection structure of the present invention is applied are described below. Embodiments 
       FIG.  1    illustrates the cross-sectional structure of a connection structure  100  according to an embodiment. The connection structure  100  includes a first member  110 , a second member  120 , a damper member  130 , and a screw  140 . Hereinafter, the connection structure  100  is described with reference to  FIGS.  2 A through  7    in addition to  FIG.  1   .  FIGS.  2 A and  2 B  illustrate the first member  110 .  FIGS.  3 A and  3 B  illustrate the second member  120 .  FIGS.  4 A to  6    illustrate the damper member  130 .  FIG.  7    illustrates the screw  140 .  FIG.  2 B  is a cross-sectional view taken along line IIB-IIB of  FIG.  2 A , viewed in the Y direction.  FIG.  3 B  is a cross-sectional view taken along line IIIB-IIIB of  FIG.  3 A , viewed in the Y direction.  FIG.  6    is a cross-sectional view taken along line VI-VI of  FIG.  4 A , viewed in the Z direction. 
     Hereinafter, an XYZ coordinate system is defined, and description is made with reference to the XYZ coordinate system. In addition, hereinafter, for convenience of description, the −Z direction side is referred to as a “lower side” or “bottom”, and the +Z direction side is referred to as an “upper side” or “top”. However, this does not represent a universal vertical relationship. In addition, the term “plan view” refers to the XY-plane view. 
     The connection structure  100  is a connection structure for connecting, via the damper member  130 , the first member  110  with the second member  120  disposed facing each other in a relatively movable manner by using the screw  140 . Hereinafter, an example configuration is described in which the second member  120  is fixed and the first member  110  is movable (displaceable) relative to the second member  120  in any 360 degree direction in the XY plane and the Z direction. For example, the first member  110  can be configured to be vibrated by a vibrating element or the like. However, the first member  110  may be fixed, and the second member  120  may be movable. Alternatively, the first member  110  and the second member  120  may be relatively movable, and the first member  110  and the second member  120  may both be movable relative to another constituent element. 
     The first member  110  includes a screw boss  111 , a screw hole  112 , and a first contact portion  113 . The first member  110  is made of, for example, resin and is an integral part of a component. However, the first member  110  may be made of a material other than resin. 
     The screw boss  111  is an example of a convex support portion, and a cylindrical lower portion  111 A that is a substantially lower half of the screw boss  111  protrudes downward with respect to a base portion  110 A of the first member  110  and is fitted into a cylindrical portion  131  of the damper member  130 . A cylindrical upper portion  111 B that is a substantially upper half of the screw boss  111  protrudes upward with respect to the base portion  110 A. While the configuration is described herein with reference to the lower portion  111 A, which is a substantially lower half of the screw boss  111 , protruding downward from the base portion  110 A, the screw boss  111  only needs to have a cylindrical portion protruding downward from a reference position or reference surface, such as the base portion  110 A. The entire screw boss  111  may protrude downward from the base portion  110 A. 
     The screw hole  112  is provided so as to extend from a lower end surface  111 A 1  of the lower portion  111 A toward the interior of the screw boss  111  and has a thread groove formed in its inner wall. The lower end surface  111 A 1  is an example of a protruding end of the convex support portion. In the present example, the screw hole  112  is provided from the interior of the lower portion  111 A to the interior of the upper portion  111 B. 
     The first contact portion  113  is an annular portion of the base portion  110 A located around the lower portion  111 A of the screw boss  111 . The first contact portion  113  is in contact with the upper surface (an example of a first contact surface) of a flange portion  132  of the damper member  130 . The lower surface of the first contact portion  113  is flat. 
     The second member  120  includes a cup portion  121 , a second contact portion  122 , and a through-hole  123 . The second member  120  is made of, for example, resin and is an integral part of a component. However, the second member  120  may be made of a material other than resin. 
     The cup portion  121  is an example of a concave support portion. The cup portion  121  includes a cylindrical wall  121 A protruding upward from a base portion  120 A of the second member  120  and a bottom wall  121 B and has a columnar recess portion  121 C thereinside. The recess portion  121 C is a portion surrounded by the wall  121 A and the bottom wall  121 B. The bottom wall  121 B is an example of a bottom portion of the concave support portion. The inner periphery of the wall  121 A of the cup portion  121  is fitted to the outer periphery of the cylindrical portion  131  of the damper member  130 . 
     While the configuration is described herein with reference to the cup portion  121  including a cylindrical wall protruding upward from the base portion  120 A, the cup portion  121  can have any shape that includes the columnar recess portion  121 C. For example, the cup portion  121  may be a columnar recess portion recessed from the upper surface of a plate-like member that is thicker than the base portion  120 A and that extends parallel to the XY plane. 
     The second contact portion  122  is an upper end portion of the cup portion  121  and is an annular portion. The second contact portion  122  faces the first contact portion  113  of the first member  110 . The upper surface of the second contact portion  122  is flat. The second contact portion  122  is in contact with the lower surface (an example of a second contact surface) of the flange portion  132  of the damper member  130 . 
     The through-hole  123  of the second member  120  is a hole that penetrates the bottom wall  121 B of the cup portion  121  in the vertical direction. The through-hole  123  is circular in plan view and is located in the center of the bottom wall  121 B in plan view. The through-hole  123  provided in the center of the bottom wall  121 B of the cup portion  121  is connected to the recess portion  121 C and penetrates the cup portion  121  in the vertical direction. The opening diameter of the through-hole  123  is smaller than the opening diameter of the upper recess portion  121 C. 
     The damper member  130  includes the cylindrical portion  131 , the flange portion  132 , ribs  133 , and projecting portions  134 . The damper member  130  is made of an elastic, deformable material, such as rubber (silicon rubber or the like). The damper member  130  is provided between the first member  110  and the second member  120  and functions as a shock-absorbing material. 
     The cylindrical portion  131  is a portion having a cylindrical shape and including a through-hole  131 A that penetrates in the axial direction (the Z direction) and an annular portion  131 B. The flange portion  132  is provided on the outer periphery of the upper end of the cylindrical portion  131 , and the ribs  133  are provided on the inner periphery and the outer periphery. The through-hole  131 A of the damper member  130  penetrates the center portion of the cylindrical portion  131  having such a configuration from the top end to the bottom end. The opening diameter of the through-hole  131 A in the center portion of the annular portion  131 B is smaller than that of the upper end portion of the cylindrical portion  131 . 
     The flange portion  132  is an annular portion provided radially outward from the outer periphery of the upper end of the cylindrical portion  131 . While the configuration is described herein with reference to the flange portion  132  provided on the outer periphery of the upper end of the cylindrical portion  131 , the flange portion  132  may be provided radially outward from the outer periphery at a position lower than the upper end of the cylindrical portion  131 . 
     The ribs  133  are an example of a first vibration absorbing portion and include ribs  133 A and  133 B. The ribs  133 A are corrugated projections provided on the inner periphery of cylindrical portion  131 , and the ribs  133 B are corrugated projections provided on the outer periphery of the cylindrical portion  131 . Each of the ribs  133 A and  133 B is provided so as to extend in the axial direction (the Z direction) of cylindrical portion  131 . Hereinafter, the ribs  133 A and  133 B are collectively referred to as “ribs  133 ” if not specifically distinguished. 
     As illustrated in  FIG.  6   , the ribs  133 A and  133 B are provided at equal intervals alternately on the inner periphery and outer periphery of the cylindrical portion  131  in the circumferential direction. The ribs  133 A and  133 B are provided in a staggered manner in the circumferential direction of the cylindrical portion  131  so as to be arranged at different positions in the circumferential direction. Each of the ribs  133  extends from the top end to the bottom end of the cylindrical portion  131  in the axial direction (the Z direction). More specifically, the upper end of the rib  133 B is in contact with the lower surface of the flange portion  132 , and the lower end of the rib  133 A is in contact with the upper surface of the annular portion  131 B at the lower end of cylindrical portion  131 . 
     The plurality of ribs  133 A protrude radially inward of the cylindrical portion  131  so as to be in contact with the outer periphery of the lower portion  111 A of the screw boss  111  when the damper member  130  is fitted into the lower portion  111 A. The plurality of ribs  133 B protrude radially outward of the cylindrical portion  131  so as to be in contact with the inner periphery of the cup portion  121  when the damper member  130  is fitted into the interior of the cup portion  121 . The ribs  133 A and  133 B absorb vibration of the first member  110  in the XY direction with respect to the second member  120 . 
     The projecting portions  134  are an example of a second vibration absorbing portion and are provided on the upper surface of the flange portion  132 . For example, four projecting portions  134  are provided on the upper surface of the flange portion  132  at equal intervals in the circumferential direction. The projecting portions  134  are, for example, conical projections. The projecting portions  134  are in contact with the first contact portion  113  of the first member  110  and are located between the first contact portion  113  and the second contact portion  122  of the second member  120  that is in contact with the lower surface of the flange portion  132  to absorb vibration of the first member  110  in the Z direction with respect to the second member  120 . 
     The above-described damper member  130  has such a size that, when the connection structure  100  is assembled as illustrated in  FIG.  1   , a gap is formed between the lower end surface of the cylindrical portion  131  of the damper member  130  (the lower surface of the annular portion  131 B) and an upper surface  121 B 2  of the bottom wall  121 B of the cup portion  121 . That is, the length in the Z direction of part of the cylindrical portion  131  that is lower than the flange portion  132  is required to be shorter than the length in the Z direction of the wall  121 A of the cup portion  121 . 
     In addition, the damper member  130  having the configuration described above can be manufactured with a mold of a vertical pull-out type. This is because there are no recesses that recess in the radial direction on the inner periphery and outer periphery of the damper member  130 . For this reason, the damper member  130  can be easily manufactured with a mold of a vertical pull-out type that has a simple structure without a lateral slide mechanism or the like. 
     The screw  140  includes a threaded portion  141 , a pillar portion  142 , a plate portion  143 , and a screw head  144 . The top end of the screw  140  is located on the upper side (the +Z direction side). The threaded portion  141  is a portion having a spiral thread groove formed thereon, and the threaded portion  141  has such a size that when screwed, it is engageable with the screw hole  112  while forming a thread groove on the wall surface of the screw hole  112  of the screw boss  111  of the first member  110 . The threaded portion  141  is an example of a top end side of the screw  140 . 
     The pillar portion  142  is located closer to the screw head  144  than the threaded portion  141 , and the diameter of the pillar portion  142  is larger than that of the threaded portion  141  and smaller than that of the through-hole  131 A of the damper member  130 . No thread grooves are formed on the outer periphery of the pillar portion  142 . The diameter of the pillar portion  142  is smaller than the opening diameter of the through-hole  123  of the second member  120 , and when the pillar portion  142  is inserted into the through-hole  123 , a gap is formed in the radial direction so that the pillar portion  142  can vibrate from side to side. The screw  140  is thus an example of a shoulder screw that integrally includes a pillar portion  142  thicker than the threaded portion  141 . 
     While the configuration is described herein with reference to the pillar portion  142  being part of the screw  140 , the pillar portion  142  may have a different form. That is, like widely used screws, a section of the screw  140  corresponding to the pillar portion  142  may be a columnar section having an outer diameter that is the same as the outer diameter of the threaded portion  141  and having a thread groove formed thereon up to the plate portion  143 , and the threaded portion  141  and the columnar section may be inserted into a cylindrical metal member having a length in the Z direction and an outer diameter that are the same as those of the pillar portion  142 . 
     The plate portion  143  is provided between the pillar portion  142  and the screw head  144 . The plate portion  143  has a larger diameter than each of the pillar portion  142  and the screw head  144  and extends radially outward beyond each of the pillar portion  142  and the screw head  144 . The diameter of the plate portion  143  is larger than the opening diameter of the through-hole  123  of the lower end of the second member  120 . 
     The screw head  144  is provided on the side of the screw  140  opposite the threaded portion  141 . That is, the screw head  144  is provided under the plate portion  143 . A plus or minus groove  144 A is provided on the lower surface of the screw head  144 . 
     To assemble the above-described connection structure  100 , the damper member  130  is fitted into the lower portion  111 A of the screw boss  111  of the first member  110  first, for example. At this time, the ribs  133 A are in contact with the outer periphery of the lower portion  111 A. Subsequently, the second member  120  is brought closer to the lower side of the first member  110 , the damper member  130  is fitted into the interior of the cup portion  121 , and the screw  140  is inserted into the through-hole  123  from below the second member  120 . 
     Subsequently, the threaded portion  141  is inserted into the screw hole  112  of the screw boss  111  and is screwed into the screw hole  112  until an upper end surface  142 A of the pillar portion  142  is brought into contact with the lower end surface  111 A 1  of the screw boss  111 . In this way, the screw  140  is screwed to the screw hole  112 . The positional relationship, in the Z direction, of the threaded portion  141 , the pillar portion  142 , and the plate portion  143  can be such that when the threaded portion  141  is screwed into the screw hole  112 , an upper end surface  143 A of the plate portion  143  is brought into contact with a lower surface  121 B 1  of the bottom wall  121 B of the second member  120  before the upper end surface  142 A of the pillar portion  142  is brought into contact with the lower end surface  111 A 1  of the screw boss  111 . That is, the length of the pillar portion  142  in the Z direction is required to be determined so that when the upper end surface  142 A of the pillar portion  142  is brought into contact with the lower end surface  111 A 1  of the screw boss  111 , the thickness (length) of the flange portion  132  of the damper member  130  in the Z direction is compressed so as to be thinner (shorter) than the initial thickness (length). 
     Due to the positional relationship of these portions, when the connection structure  100  is assembled as illustrated in  FIG.  1   , the flange portion  132  and the projecting portions  134  of the damper member  130  are sandwiched between the first contact portion  113  of the first member  110  and the second contact portion  122  of the second member  120  and are urged in the Z direction so as to be slightly compressed and have an initial elasticity. In addition, the ribs  133 A of the damper member  130  are in fitting contact with the outer periphery of the screw boss  111 , and the ribs  133 B of the damper member  130  are in fitting contact with the inner periphery of the cup portion  121 . For this reason, each of the ribs  133  of the damper member  130  has the initial elasticity. 
     Furthermore, a gap is formed between the lower end surface of the damper member  130  and the upper surface  121 B 2  of the bottom wall  121 B of the cup portion  121 . Still furthermore, a gap is formed between the outer periphery of the pillar portion  142  of the screw  140  and the inner periphery of the through-hole  123 , and the upper end surface  143 A of the plate portion  143  is in contact with the lower surface  121 B 1  of the bottom wall  121 B. 
     Thus, when after the connection structure  100  is assembled, neither a force in a direction of displacing the first member  110  relative to the second member  120  in the XY plane nor the force pressing the first member  110  downward is exerted on the first member  110 , the position of the first member  110  is the initial position that is balanced by the initial elastic force of the damper member  130  inside. 
     Therefore, when the force in the direction of displacing the first member  110  in the XY plane relative to the second member  120  is externally exerted, the cylindrical portion  131  and the ribs  133 A and  133 B are further elastically deformed and, thus, the first member  110  is displaced relative to the second member  120  in the XY plane. The amount of displacement of the first member  110  is the amount of displacement caused by the elastic deformation of the cylindrical portion  131  and the ribs  133 A and  133 B between the outer periphery of the screw boss  111  and the inner periphery of the wall  121 A of the cup portion  121 . Since the ribs  133 A and  133 B are arranged so as to be corrugated inwardly and outwardly with respect to the cylindrical portion  131  in plan view, the ribs  133 A and  133 B are compressed to deform in the radial direction and, thus, are displaced in the radial direction. At this time, the cylindrical portion  131  is also compressed in the radial direction and contracts slightly. The displacement of the damper member  130  in the radial direction enables the first member  110  to be displaced relative to the second member  120  in the XY plane. When the force in the direction of displacing the first member  110  in the XY plane is removed, the elastic deformation returns to its original shape due to the elastic force of the ribs  133 A and  133 B and the cylindrical portion  131 , and the first member  110  returns to its initial position relative to the second member  120 . 
     When a downward pressing force is exerted on the first member  110  with respect to the second member  120 , a force is exerted on the projecting portions  134 , resulting in compression of the projecting portions  134  in the vertical direction and deformation of the flange portion  132 . Thus, the projecting portions  134  and the flange portion  132  deform such that they are thinner than the total thickness (the total length in the Z direction) of the projecting portion  134  and the flange portion  132  before deformation. Since the four projecting portions  134  are provided on the upper surface of the annular flange portion  132  at equal intervals in the circumferential direction, the flange portion  132  is subjected to the downward force at equal intervals in the circumferential direction. Therefore, the flange portion  132  is deformed so that a region around the region where the projecting portions  134  are provided is more downwardly distorted (becomes thinner) than the region where the projecting portions  134  are not provided. 
     When the projecting portions  134  and the flange portion  132  are deformed in this manner, the screw  140  can be displaced downward together with the first member  110  relative to the second member  120 , since the pillar portion  142  of the screw  140  is only inserted to the through-hole  123  with a clearance therebetween and is not engaged with the through-hole  123 . 
     When, as described above, the downward pressing force is exerted on the first member  110 , the first member  110  is displaceable relative to the second member  120 . When the force pressing the first member  110  downward is removed, the elastic deformation of the projecting portions  134  and the flange portion  132  returns to its original shape due to their elastic forces, and the first member  110  returns to its initial position relative to the second member  120 . 
     According to the connection structure  100  described above, the first member  110  and the second member  120  can be formed integrally, and the damper member  130  can be easily manufactured using a mold of a vertical pull-out type. As described above, to assemble the connection structure  100 , the damper member  130  can be fitted into the lower portion  111 A of the screw boss  111  of the first member  110 , the second member  120  can be brought closer to the lower side of the first member  110 , the damper member  130  can be fitted into the interior of the cup portion  121 , the screw  140  can be inserted into the through-hole  123  from below the second member  120 , and the threaded portion  141  can be screwed into the screw hole  112 . In this manner, the connection structure  100  can be manufactured very easily. 
     Therefore, an easily manufacturable connection structure  100  can be provided. In addition, when the damper member  130  is assembled to the first member  110  and the second member  120 , the damper member  130  can be easily assembled by moving only in the vertical direction. For this reason, automatic assembly machines can be readily employed, although automatic assembly machines are difficult to use for the structure that requires a manufacturing method including movement, such as lateral insertion. As a result, the manufacturing costs can be reduced. 
     In addition, since the damper member  130  includes the ribs  130 A and  130 B and the projecting portion  134 , displacement of the first member  110  relative to the second member  120  in the lateral direction (a direction in the XY plane) and the longitudinal direction (the Z direction) can be accommodated, and vibration and the like in the lateral and longitudinal directions can be absorbed. 
     In addition, since the ribs  133 A and  133 B are provided in a staggered manner in the circumferential direction of the cylindrical portion  131  and are located in different positions in the circumferential direction, the ribs  133 A and  133 B can easily deform elastically in the radial direction and, thus, are displaceable in any direction in the XY plane of the first member  110  so as to absorb vibrations and the like. Furthermore, since the ribs  130 A and  130 B are provided at equal intervals in the circumferential direction of the cylindrical portion  131 , displacement in the lateral direction (a direction in the XY plane) and absorption of vibrations and the like can be achieved in a well-balanced manner. 
     In addition, since the damper member  130  includes the projecting portion  134  projecting from the upper surface of the flange portion  132 , the damper member  130  can be easily elastically deformed in the longitudinal direction (the Z direction), enabling more reliable displacement in the longitudinal direction (the Z direction) and absorption of vibration and the like in the longitudinal direction (the Z direction). 
     In addition, the first member  110  includes the screw boss  111  having a screw hole  112  formed therein, a screw  140  is inserted into the through-hole  123  of the second member  120 , and assembling is achieved with the first member  110  and the second member  120  pinching the flange portion  132  of the damper member  130 . As a result, assembling can be achieved with the flange portion  132  being compressed to a certain extent and, thus, the flange portion  132  can have initial elasticity at the initial position. 
     During assembly of the connection structure  100 , the amount of compression of the flange portion  132  and the projecting portion  134  of the damper member  130  in the Z direction between the first contact portion  113  and the second contact portion  122  can be adjusted by the position at which the upper end surface  142 A of the pillar portion  142  of the screw  40  is in contact with the lower end surface  111 A 1  of the screw boss  111 . For example, the amount of compression can be adjusted by changing the length of the pillar portion  142  in the Z direction, so that the initial elastic force of the damper member  130  can be set to a desired value at the initial position of the damper member  130 . 
     While the above configuration has been described with reference to the damper member  130  including the ribs  133 A and  133 B, the configuration may include either the ribs  133 A or the ribs  133 B. 
     While the above configuration has been described with reference to the configuration in which the flange portion  132  includes the projecting portions  134  on the upper surface of the flange portion  132 , the projecting portions  134  may be provided on the lower surface of the flange portion  132 . 
     While the connection structure according to an exemplary embodiment of the present invention has been described above, the present invention is not limited to the specifically disclosed embodiment, and various changes and modifications can be made without departing from the scope of the claims.