JP5467338B2 - Engagement mechanism - Google Patents

Description

  The present invention relates to an engagement mechanism for connecting members to each other.

  Conventionally, various engagement mechanisms for connecting members to each other are known, such as those using bolts and nuts and those having an uneven engagement structure (see, for example, Patent Document 1).

  However, it is difficult to associate these parts with each other unless the positions to be joined are accurately positioned. For this reason, when an engagement mechanism is used which is applied to a portion that cannot be visually observed at the time of mounting, alignment is difficult. In particular, when engaging members that are likely to be distorted, the engagement position is slightly different for each individual, so there is a problem that assembly requires skill and automation is difficult.

  In addition, when the members are forcibly positioned and coupled to each other, unexpected stress may remain inside the engaging portion, which may cause a problem that the finished product is adversely affected.

JP 2009-45156 A

  The present invention solves the above-described problems, facilitates the engaging operation, and allows the slight movement in the other direction while reliably preventing the relative separation between the members in the engaged state. An object is to provide an engagement mechanism.

The present invention employs the following configuration in order to solve the above-described problems. That is, the engagement mechanism according to the present invention is for joining the first member and the second member to each other, and is provided on the first member, and is a plurality of sheets that can be elastically deformed in the thickness direction. of the receiving part of the cantilever elastic pieces composed by arranging a frustum shape, the cantilever elastic pieces with the engaging hole formed by the free end edge of the second mounted members the cantilever elastic pieces It is premised that it has a protrusion that engages using elastic deformation.

  Here, the truncated cone shape refers to a truncated cone-shaped cone shape, and may be a truncated cone shape or a polygonal shape such as a truncated quadrangular pyramid shape or a truncated triangular pyramid shape. . The truncated cone shape is configured by arranging a plurality of curved plate-shaped cantilever elastic pieces, and the truncated polygonal shape is configured by arranging a plurality of non-curved plate-shaped cantilever elastic pieces. Configured.

  If it is such, a member can be easily combined by fitting the receiving part provided in the 1st member, and the protrusion provided in the 2nd member. That is, even if there is some error in the relative position between the first member and the second member to be joined, the projection is guided along the cantilever elastic pieces arranged in a truncated cone shape. For this reason, even when the engaging mechanism is applied to a portion that cannot be visually observed at the time of mounting, the engaging operation can be easily performed. Further, in the state where they are engaged, the cantilever is formed while the relative separation between the first member and the second member is reliably prevented by the engagement between the truncated cone-shaped receiving portion and the protrusion. Since the elastic piece is elastically deformable in the thickness direction, movement in a direction other than the direction in which the first member and the second member are separated can be allowed.

  One aspect of the one that can be easily engaged by guiding the protrusion and is difficult to be relatively separated in the engaged state is a receiving portion in which a plurality of cantilever elastic pieces are arranged in a frustoconical shape. It is preferable.

  Further, as the protrusions that engage with the receiving portion, a shaft portion that penetrates the engagement hole and a retaining collar portion that is provided at the tip of the shaft portion and is larger than the inner diameter of the engagement hole are provided. What comprises is preferable.

  When the cantilever elastic pieces facing each other are elastically deformed until they are positioned on a single plane, it is preferable that the distance between the free ends facing each other is smaller than the diameter of the shaft portion of the protrusion. In such a case, once the protrusions are fitted into the receiving part, the cantilevered elastic piece is opposite because the free edge of the cantilevered elastic piece hits against the shaft part of the protrusion even if they are pulled away from each other. Does not flex to the side. For this reason, it is possible to prevent the projection from coming off from the receiving portion.

In the present invention , a headed screw is screwed onto a boss projecting from the second member, and the projection includes a shaft portion including a shaft of the boss and a headed screw, and a head portion of the headed screw. all SANYO having a distance between the free edges of opposed when elastically deformed until positioned on one plane the cantilever elastic pieces facing each other, smaller than the diameter of the shaft portion, and, characterized in that it is set rather larger than the diameter of the shaft of the headed screw. Such things der because the headed slightly loosening the screws, it is possible to pull out the projection from the receiving portion by exposing the screw shaft portion than the thickness of the cantilever elastic pieces.

  As an example of the coupling between the members using the engagement mechanism described above, it is for attaching the back inner shell of the chair to the back outer shell, the first member is a member on the back inner shell side, What the said 2nd member is a member by the side of a back outer shell is mentioned.

  As another example, an armrest is attached to an armrest body, the first member is an armrest side member, and the second member is an armrest body side member. Is mentioned.

  Since the present invention is configured as described above, the engagement operation is facilitated even if there is some error in the relative position between the members to be coupled, and the relative separation between the members is reduced in the engaged state. Minor movements in other directions can be tolerated while reliably preventing.

1 is an overall perspective view showing an embodiment of the present invention. The disassembled perspective view which shows the front side of the backrest of the embodiment. The disassembled perspective view which shows the front side of the backrest of the embodiment. The disassembled perspective view which shows the back side of the back unit of the embodiment. The disassembled perspective view which shows a part of backrest of the embodiment. The partial expansion perspective view which shows a part of back unit in the embodiment. The principal part expansion perspective view of the back unit in the embodiment. The principal part enlarged front view of the back unit in the embodiment. XX sectional drawing in FIG. The YY sectional view taken on the line in FIG.

  Hereinafter, an embodiment in which the present invention is applied to a synchro tilt type office rotary chair will be described with reference to the drawings.

  As shown in FIG. 1, the chair includes a leg 1, a support base 2 that is supported by the upper part of the leg 1 and can be turned horizontally, a seat 3 that is disposed on the support base 2, A seat 4 held by the seat receiver 3, an armrest 9 extending from the lower side of the seat receiver 3 to the left and right, a back support bar 5 provided on the support base 2 so as to be able to tilt backward, and the back And a backrest 6 attached to the support 5.

  As shown in FIG. 1, the leg portion 1 includes a leg blade type leg base 11 having casters and a leg column 12 erected at the center of the leg base 11. The leg strut 12 is a normal one mainly composed of a gas spring, and the support base 2 is attached to the upper end of the leg strut 12.

  As shown in FIG. 1, the support base portion 2 is supported by the leg portion 1 so as to be able to turn horizontally, and includes a housing 21 attached to the leg column 12 and a backrest support penetrating the housing 21. And a tilting reaction force generating mechanism (not shown) that applies a force to the main shaft 22 to generate an elastic repulsive force with respect to the backward tilting operation of the backrest 6. The tilt reaction force generation mechanism is configured to be able to apply an elastic repulsion force in the rotational direction to the main shaft 22 using a coil spring, a gas spring, or the like (not shown). Is omitted.

  As shown in FIG. 1, the seat receiver 3 is a disk-like one that supports the seat 4 on the upper surface, and its front end side is supported by the support base 2 so as to be movable back and forth, and its rear end side is the back support rod. 5 is supported so as to be capable of relative rotation in the vicinity of the base end. With this configuration, the seat 4 disposed on the seat receiver 3 sinks at a constant angle ratio with respect to the back tilting operation of the backrest 6, in other words, a synchro tilting operation is realized. It has become.

  As shown in FIG. 1, the armrest 9 includes an elbow strut 91 whose base end is attached to the seat support 3 and an elbow rest 92 supported by the elbow strut 91. The left and right armrests 9 have a symmetrical shape.

  As shown in FIG. 1, the back support rod 5 is generally L-shaped in a side view, and a lower back frame 52 whose base end is attached to the main shaft 22 of the support base 2 so as to be able to tilt backward, An upper back frame 51 attached to the tip of the lower back frame 52 via a support shaft 53 so as to be able to tilt backward is provided. The lower back frame 52 is made of metal, and the outside is covered with a cover 521. The outer surface of the cover 521 is provided so as to extend forward from a position continuous with the outer surface of the upper back frame 51 to the lower surface of the seat 4. The upper back frame 51 is integrally formed of synthetic resin, and extends substantially vertically when the backrest 6 is in a standing state, and supports the upper portion of the backrest 6 with this upper end portion. That is, in this embodiment, the lower part of the backrest 6 is fixed to the lower back frame 52, while the upper part of the backrest 6 is supported by the upper back frame 51 so as to be slidable in the vertical direction. In addition, the upper back frame 51 can be tilted within a certain angle range independently of the lower back frame 52, and the upper back frame 51 can be tilted with respect to the lower back frame 52. The upper back frame 51 is elastically biased forwardly by a spring (not shown) with respect to the lower back frame 52. In this embodiment, a tilting prohibiting mechanism (not shown) is provided between the lower back frame 52 and the support base 2, and a free locking state that allows the lower back frame 52 to tilt with respect to the support base 2, or the lower back frame 52 is desired. An arbitrary position fixed state in which tilting is prohibited at an angle of can be taken. Since the structure of the tilt prohibiting mechanism is a normal one, description thereof is omitted.

  The backrest 6 is formed by mounting a back unit 8 on the front surface of the back outer shell 7 as shown in FIGS.

  As shown in FIGS. 1 to 3 and 5, the back outer shell 7 is an integrally molded product made of synthetic resin, and has a protruding top portion that protrudes most forward in the middle in the vertical direction, from the protruding top portion. A shell main body 70 having a curved shape rearward is mainly formed, and a lower attachment portion 71 and an upper attachment portion 72 for attaching the back outer shell 7 to the back support rod 5 on the back side of the shell main body 70. It has. The lower attachment portion 71 protrudes rearward from the lower portion of the shell body 70 and is fixed to the upper end portion of the lower back frame 52 using a fastening tool such as a screw (not shown). The upper mounting portion 72 has a concave shape for accommodating the slide engagement mechanism C, and the back outer shell 7 and the back support rod 5 are connected via a slide engagement mechanism C (not shown) mounted on the upper mounting portion 72. An upper end portion of the upper back frame 51 is connected to be movable in the vertical direction.

  An upper end mounting portion 73 and a lower end mounting portion 74 for mounting the back unit 8 are provided on the front side of the back outer shell 7. The upper end mounting portion 73 is formed by projecting a plurality of hooking claws 731 on the upper portion of the shell main body 70 at intervals in the left-right direction. The lower end attaching portion 74 includes a central projecting portion 741 having a bifurcated portion projecting from the lower center of the shell main body 70, and claw receiving portions 742 provided at both lower ends of the shell main body 70.

  As shown in FIGS. 2 to 4, the back unit 8 includes a back inner shell 81, a headrest 82 directly supported by the back inner shell 81, and a bag-like exterior that encloses the headrest 82 and the back inner shell 81. And a material 83.

  As shown in FIGS. 3 to 6, the back inner shell 81 is an integrally molded product made of a synthetic resin having substantially the same outer shape as the back outer shell 7, and is a protrusion that protrudes most forward in the middle in the vertical direction. The shell main body 810 which has a top part and makes the shape curved back from the protrusion top part is comprised mainly. The shell main body 810 is provided with an upper end attachment portion 811 and a lower end attachment portion 812 for attaching the back unit 8 including the back inner shell 81 to the back outer shell 7. The upper end mounting portion 811 is formed by forming a plurality of claw-hanging holes 813 provided in the upper portion of the shell main body 810 corresponding to the hooking claw 731. The upper portion of the back inner shell 81 is attached to the upper portion of the back outer shell 7 by being hooked so as to be relatively displaceable in the vertical direction. The lower end mounting portion 812 includes a center insertion portion 814 provided at a lower center portion of the shell body 810 and claw portions 815 provided at both lower side portions of the shell body 810. The central insertion portion 814 has a horizontal member 817 disposed at an intermediate position of the window 816, and the bifurcated portion of the central protrusion 741 of the back outer shell 7 inserted into the window 816 is engaged with the horizontal member 817. By combining them, the center of the lower end of the back inner shell 81 is attached to the lower end of the back outer shell 7. Further, the claw portion 815 has a tip bent outward, and the claw portion 815 is engaged with the claw receiving portion 742 of the back outer shell 7 by using the temporary elastic deformation of the back inner shell 81. Thus, both ends of the lower end portion of the back inner shell 81 are attached to the lower end portion of the back outer shell 7.

  The headrest 82 is directly supported on the back inner shell 81 configured as described above.

  As shown in FIGS. 3 to 8, the headrest 82 is an integrally molded product made of synthetic resin. The headrest body 823 and a base provided in a plate shape from the lower end edge of the headrest body 823 via a bent portion 822. 821. Specifically, the headrest body 823 is curved so that the central portion protrudes forward in side view and the central portion is recessed in plan view, and includes a plurality of horizontal slits 825 in parallel. . The bent portion 822 is formed at the boundary portion between the headrest body 823 and the base 821, and has a shape that is bent in a square shape in a side view so that a wire groove is formed on the front side. The curved shape on the back side of the bent portion 822 is matched with the curved shape of the upper edge of the back inner shell 81. The base 821 is a plate that can be attached to the front surface of the back inner shell 81, and is attached to the back inner shell 81 using a plurality of bolts b. Specifically, the base 821 is fixed to the back inner shell 81 by screwing bolts b penetrated from the back side of the back inner shell 81 to nuts N attached to a plurality of locations of the base 821. It has become.

  In this embodiment, the following component mounting structure A is adopted in order to make the mounting portion between the base 821 and the back inner shell 81 as thin as possible. As shown in FIGS. 4 to 7, the component mounting structure A is for mounting a nut N, which is a mounted component, on a base 821, and the base 821 is provided with a main recess A11 and a sub-recess A12. A part holding claw A15 is provided adjacent to the partition A13 through which the nut N inserted into the main recess A11 is engaged using elastic deformation of the partition A13. That is, the nut N is of a so-called T-type nut type in which a flange N2 is provided at one end of a shaft-shaped nut body N1. The main concave portion A11 has a bottom with which the flange portion N2 can be fitted, and has a through portion A14a for penetrating the nut main body N1 to the back side of the base 821 at the center of the bottom wall A14. . The sub-recess A12 is a pair of long holes provided so as to penetrate the back surface side of the base 821 on both sides of the main recess A11. The partition wall A13 is formed between the main recess A11 and the paired sub-recesses A12, A12, and has a thickness that can be elastically deformed in the thickness direction. A claw A15 protruding from the front side of 821 is provided. When the nut N is inserted into the main recess A11, these claws A15 are engaged with the outer surface side of the flange portion N2 by using temporary elastic deformation of the partition wall A13, and the nut N is It can be held in the recess A11.

  The exterior material 83 is attached to the back inner shell 81 and the headrest 82 that are integrated with each other in this manner.

  As shown in FIGS. 1 to 4, the exterior material 83 includes a cushion 831 made of molded urethane or the like, and a tension fabric 832 that covers the surface side of the cushion 831. The exterior material 83 is drawn into the back inner shell 81 side at the bent portion 822 of the headrest 82, and a boundary 833 that partitions the headrest main body region and the back inner shell region is formed. The configuration of the retracting portion of the exterior material 83 will be specifically described as follows. In other words, the exterior material 83 is a bag-shaped member including a front surface portion 83F for covering the front surface of the back unit 8 and a back surface portion 83B for covering the back surface of the back unit 8, and includes a headrest 82 and a back inner shell. The lower side is opened so that 81 can be wrapped from the upper side. A drawing wire (not shown) is sewn into a portion corresponding to the boundary 833 of the front surface portion 83F, and the portion corresponding to the boundary 833 of the front surface portion 83F can be drawn into the drawing portion 824 using this wire. I can do it. The back surface portion 83B has an upper opening 83B1 corresponding to the upper end mounting portions 73 and 811, a lower opening 83B2 corresponding to the lower end mounting portions 74 and 812, and an intermediate opening 83B3 corresponding to the engagement mechanism C described later. Is drilled.

  In the chair configured as described above, the lift restriction that restricts the relative separation in the thickness direction while allowing the relative movement in the surface direction to the back outer shell 7 at the portion located between the upper part and the lower part of the back inner shell 81. It is supported via an engagement mechanism C. The engaging mechanism C includes a receiving portion C1 provided on the back inner shell 81 side and a plurality of cantilever elastic pieces C11 that are elastically deformable in the thickness direction and arranged in a truncated cone shape, and the back outer shell 7 side. And an engaging hole C12 formed by a free end edge C111 of the cantilever elastic piece C11, and a projection C2 that engages using the elastic deformation of the cantilever elastic piece C11. Specifically, the receiving portion C1 is formed integrally with the base 821 of the headrest 82 that is immovably attached to the back inner shell 81 so that the free end C111 side comes forward from the base end edge. A plurality of cantilevered elastic pieces C11 inclined to each other are arranged in a frustoconical shape bulging forward. Further, holes 818 for opening the receiving portion C1 to the back side of the back unit 8 are provided in portions corresponding to the receiving portion C1 in the back inner shell 81 and the back surface portion 83B of the exterior material 83, respectively. The protrusion C2 inserted through these holes 818 is engaged with the receiving portion C1. The protrusion C2 protrudes from the front side of the back outer shell 7, and has a shaft portion C21 slightly smaller in diameter than the engagement hole C12 and the engagement hole C12 provided at the tip of the shaft portion C21. And a retaining collar C22 that is larger than the inner diameter. A guide surface C221 for smoothly pushing the cantilever elastic piece C11 is formed at the tip of the retaining collar C22. The protrusion C2 may be provided integrally with the back outer shell 7 or may be provided separately.

  In the chair constructed as described above, the headrest 82 is attached to the back inner shell 81, the back inner shell 81 and the headrest 82 are wrapped with the exterior material 83, and the boundary 833 of the exterior material 83 is drawn into the bent portion 822. Complete the spine unit 8 with. After that, the back unit 8 is attached to the front surface of the back outer shell 7. In attaching the back unit 8 to the back outer shell 7, first, the upper end mounting portion 811 of the back inner shell 81 is engaged with the upper end mounting portion 811 of the back inner shell 81, and the lower end mounting portion 812 of the back inner shell 81 is engaged with the back. The lower end mounting portion 74 of the outer shell 7 is engaged. In this state, the intermediate portion of the back unit 8 is pressed toward the back outer shell 7 so that the projection C2 is engaged with the receiving portion C1 of the engagement mechanism C.

  Next, the operation of this chair will be described. When the tilt prohibiting mechanism (not shown) is operated and set to the free locking state, a load is applied to the backrest 6, so that the entire back support 5 against the urging force of the tilt reaction force generating mechanism against the support base 2. You can tilt backwards. In addition, the seat 4 also performs a sync tilt operation. On the other hand, when the tilt prohibiting mechanism is operated and set to a fixed state at an arbitrary position, a load is applied to the backrest 6, whereby the lower back frame 52 is fixed to the support base 2, and only the upper back frame 51 is the lower back frame. The tilting is allowed with respect to 52.

  Thus, in a chair that can be used by switching to various modes, various loads act on the back outer shell 7 and the back inner shell 81 of the backrest 6. In particular, in this embodiment, since the backrest 6 is supported by the single back support 5, a torsional load or the like may act on the back outer shell 7 and the back inner shell 81. However, in this chair, since the back outer shell 7 and the back inner shell 81 are connected at the upper end portion and the lower end portion, the back outer shell 7 and the back inner shell 7 are compared with the case where both the shells 7 and 81 are completely integrated. The degree of freedom of deformation of the inner shell 81 can be increased. That is, both shells 7 and 81 cooperate with each other to bend back and forth, but against left and right torsion, both shells 7 and 81 move relative to each other in the surface direction and flexibly deform. For example, it is possible to impart various deformation characteristics to the backrest 6. Moreover, in this chair, since the engagement mechanism C is used in the middle part of the shells 7 and 81, the relative separation in the front-rear direction is limited while allowing relative movement in the surface direction. Although the deformation can be realized, the intermediate portion can be prevented from being lifted. Further, since the receiving portion C1 has a truncated conical shape, when the back inner shell 81 is attached to the back outer shell 7, even if there is a slight misalignment between the center of the receiving portion C1 and the center of the protrusion C2. By pressing both, the tip of the projection C2 is guided to the engagement hole C12 of the receiving portion C1, and the engagement can be completed. Therefore, even when the engagement mechanism C is not visible, it can be easily attached only by the pressing operation.

  With the above-described configuration, the engagement mechanism C according to the present embodiment is used to couple the back inner shell 81 and the back outer shell 7 to each other. A receiving portion C1 in which a plurality of cantilever elastic pieces C11 which are provided on a base 821 of a headrest 82 provided on the side and are elastically deformable in the thickness direction are arranged in a frustoconical shape; Since the protrusion C2 is engaged with the engagement hole C12 formed by the free end edge C111 of the cantilever elastic piece C11 using the elastic deformation of the cantilever elastic piece C11, the receiving portion C1 is provided. The shells 7 and 81 can be easily coupled to each other by fitting the projection C2 and the projection C2. At this time, even if there is some error in the relative position between the shells 7 and 81 to be joined, the engaging operation becomes easy, and in the engaged state, the relative separation between the shells 7 and 81 is ensured. While preventing, minor movements in other directions are acceptable.

  In particular, in this embodiment, since the receiving part C1 is looked at the back side of the back unit 8, when engaging with the protrusion C2 of the back outer shell 7, the engaging mechanism C cannot be seen. . However, since such an engagement mechanism C is used, it can be easily attached only by pressing the back unit 8 against the back outer shell 7 side.

  Further, since the receiving portion is provided integrally with the base 821 of the headrest 82, the number of parts can be reduced, and the engagement mechanism C can be prevented from becoming complicated. Furthermore, since the cantilever elastic piece C11 can be formed of the same synthetic resin as the headrest 82, its elastic deformation characteristics can be utilized.

  The present invention is not limited to the embodiment described above, and various modifications can be made.

  For example, the engagement mechanism according to the present invention can be used not only for connecting the back outer shell and the back inner shell of the chair but also for attaching the armrest to the armrest body. In this case, the receiving portion may be provided on the member on the armrest side as the first member, and the protrusion may be provided on the member on the armrest main body side as the second member. If it is such, it can be engaged by fitting the protrusion provided in the member on the armrest side in advance and the receiving part provided on the armrest main body side. Therefore, even if the mounting position is slightly shifted when the armrest is attached to the armrest body, the projection is guided along the cantilever elastic pieces arranged in a truncated cone shape, so that proper positioning can be easily performed. Even when such an engagement mechanism is not visible, it can be easily attached only by pressing operation. The first member may be provided with the receiving portion on the armrest body side member, and the second member may be provided with the protrusion on the armrest side member. In this case, the same effect can be obtained. Can do.

  Further, in the present embodiment, the cantilever elastic piece is not limited to the one made of synthetic resin, but can be variously changed as long as it is made of rubber and can be elastically deformed in the thickness direction. In addition, the receiving portion is not only provided integrally with the mounting member, but may be a member that is separately attached to the mounting member as a receiving portion including a cantilever elastic piece.

  Although the present embodiment has been described in detail above, the present invention is not limited to the above-described embodiment, and the specific configurations of other parts can be variously modified without departing from the spirit of the present invention.

C ... engaging mechanism C1 ... receiving portion C11 ... cantilever elastic piece C111 ... free end edge C12 ... engaging hole C2 ... projection C21 ... shaft portion C22 ... retaining collar 7 ... back outer shell 81 ... back inner shell

Claims (6)

An engagement mechanism for joining a first member and a second member to each other, wherein a plurality of cantilever elastic pieces provided on the first member and elastically deformable in a thickness direction are arranged in a truncated cone. a receiving portion comprising by arranging the shape, the cantilever elastic pieces with the engaging hole formed by the free end edge of the provided in the second member to be joined to the first member and the cantilever elastic pieces Ri Na and and a projection each other involved by utilizing elastic deformation,
A headed screw is screwed onto a boss projecting from the second member, and the projection has a shaft portion composed of a shaft of the boss and the headed screw, and a head portion of the headed screw. And
When the cantilever elastic pieces facing each other are elastically deformed until they are located on one plane, the distance between the opposing free ends is smaller than the diameter of the shaft portion, and the diameter of the shaft of the headed screw An engagement mechanism characterized by being set larger . The engagement mechanism according to claim 1, wherein the receiving portion includes a plurality of cantilever elastic pieces arranged in a frustoconical shape. The said protrusion is provided with the axial part penetrated to the said engagement hole, and the retaining collar part provided in the front-end | tip of this axial part and larger than the internal diameter of the said engagement hole. Engagement mechanism. The engagement according to claim 1, 2 or 3, wherein when the cantilever elastic pieces facing each other are elastically deformed until they are located on one plane, the distance between the free ends facing each other is smaller than the diameter of the shaft portion of the protrusion. mechanism. 2. A chair for attaching a back inner shell of a chair to a back outer shell, wherein the first member is a member on the back inner shell side, and the second member is a member on the back outer shell side. The engagement mechanism according to 2, 3, or 4. The elbow be for attachment to the armrest body, said first member is a member of the elbow side, claim 1, 2, 3 or 4 wherein the second member is a member of the armrest body The engagement mechanism as described.

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