JP6555970B2 - Joining structure of chair support and seat and chair provided with the joining structure - Google Patents

Description

  The present invention relates to a coupling structure for coupling a column to which a leg of a chair is attached and a seat support that supports a seat body, and a chair provided with such a coupling structure, in particular, an office chair.

  Conventionally, as a general office chair, for example, there is one shown in a perspective view of FIG. The office chair 1 shown in FIG. 9 includes, as main components, a plurality of legs 8 each having a caster 9 at the tip, and each leg 8 standing upward and extending radially at the lower end. 8, a support 2 having base ends fixed at equal intervals in the circumferential direction, a seat receiving body 4 provided at the upper end of the support 2, a seat 7 attached to the seat receiving body 4 in a fixed state, and the seat The backrest 5 is disposed behind the body 7 and is spring-supported so as to be tiltable backward with respect to the seat receiving body 4 (see Patent Document 1). There has also been proposed a synchronous type chair in which the seat body 7 can be moved back and forth in conjunction with the back tilt of the backrest 5.

  The seat receiving body 4 of the office chair 1 equivalent to the office chair shown in FIG. 9 and its peripheral structure are shown in FIG. 10 which is a perspective view and FIG. 11 which is a sectional view. As shown in FIGS. 10 and 11, the support column 2 is disposed in the cover body 2 a that can be expanded and contracted in the height direction, and the height of the chair 1, that is, the seat body 7 and the backrest 5. And a gas spring 3 that can be adjusted in height. The gas spring 3 has a main body 3a whose lower end is fixed to the base of each leg 8, and a plurality of stages of rods 3b that are slidably fitted into the main body 3a and extend upward. A seat main body 4 is fixed to the upper end of the rod 3b. By extending and contracting each stage of the rod 3b with respect to the main body 3a, the seat receiving main body 4 and the seat body 7 and the backrest 5 provided thereon can be moved up and down integrally.

  As the gas spring 3, a conventionally known gas spring with a lock mechanism is applied. A detailed description of the internal structure of the gas spring locking mechanism and the like is omitted here. As a basic action of the gas spring 3, by pressing an operation button 3c provided at the upper end of the uppermost rod 3b, the rod 3b can be expanded and contracted with respect to the main body 3a, and the seat body 7 and The height of the backrest 5 can be adjusted. When the pressing of the operation button 3c is released, the expansion and contraction of the rod 3b with respect to the main body 3a is restricted (locked), so that the height of the seat body 7 and the backrest 5 can be set to the height selected at the time of the release. .

  The seat receiving body 4 is made of a metal molding material formed in a tray shape with an upper opening, and the seat body 7 is fixed to the seat receiving body 4 in mounting holes 16 formed at the four corners of the opening. A fixing bolt 15 is attached. On the lower surface of the seat shell 6 provided on the lower side of the seat body 7, rectangular flat surfaces 26 surrounded by frame-like ribs 23 slightly projecting downward are formed, and at the four corners of the flat surface 26. Screw holes are formed. The seat receiving body 4 is fixed to the seat shell 6 by screwing a fixing bolt 15 attached to the seat receiving body 4 into the screw hole of the seat shell 6.

  In the center of the plate-like bottom of the seat receiving body 4, a through-hole 19 is formed through which the upper part of the uppermost rod 3 b of the gas spring 3 passes. A gas receiving base 18 that forms a box-like structure with the seat receiving body 4 is fixed to the center of the seat receiving body 4. A through hole 20 that is concentric with the through hole 19 when viewed along the axial direction of the rod 3 b is formed at the center position of the gas receiving base 18. A peripheral upper surface 18 a formed in a flat shape of the gas cradle 18 is disposed to face the seat shell 6. The rod 3b has a tip inserted through the lower through-hole 19 to the upper through-hole 20, and the operation button 3c provided at the upper end is exposed above the upper surface 18a of the gas receiving base 18. . The seat receiving body 4 is fixed to the upper end of the rod 3b via the gas receiving base 18, and the seat receiving body 4 moves up and down as the rod 3b expands and contracts with respect to the body portion 3a. The cover body 2a covering the periphery of the gas spring 3 is configured to be nested in the vertical direction, and expands and contracts as the seat main body 4 moves up and down, but does not support the load acting on the seat main body 4. Depending on the chair, the cover body 2a may be omitted.

  A vertical groove 11 that accommodates the operation lever 12 so as to be movable in the vertical direction is formed on, for example, the left side surface of the seat receiving body 4 when the chair 1 is viewed from the front. The operation lever 12 is a member for pressing the operation button 3 c of the gas spring 3. The operation lever 12 has a handle 21 provided at one end and a metal round bar 13 provided with an action portion 13a at the other end, and a pivot fixed to the round bar 13 in a direction perpendicular to the round bar. 14. The action portion 13a is configured such that the tip of the round bar 13 is formed in a plate shape in order to widen the surface for pressing the operation button 3c. A groove 10 into which the pivot 14 can be fitted is formed on the lower surface of the seat shell 6, and the pivot 14 is sandwiched between the groove 10 of the seat shell 6 and the upper portion of the seat receiving body 4, thereby forming a rotation support portion 25. Yes. A curved portion 22 is formed in the vicinity of the action portion 13 a in the round bar 13, and the pivot 14 is joined to the vicinity of the curved portion 22 by welding.

  As a connecting structure between the seat frame and the support column, the cylinder tube seat mounting part, which is the upper end of the support column, is formed into a truncated cone shape with the upper apex and its vicinity cut off, and its peripheral surface is a convex cone There is a seat frame in which a mounting concavity having a concave conical surface complementary to the convex conical surface of the seat mounting portion is provided to fit both conical shapes (patent) Reference 2 and FIG. 4). The mounting recess is formed in a shell shape having a uniform thickness except for a key portion described later, and is fixed to the seat frame by means such as welding. When the seat frame and the cylinder tube are coupled, the convex conical surface and the concave conical surface complementary to the convex conical surface are fitted to each other, thereby fitting the seat mounting portion of the cylinder tube and the mounting concave portion of the seat frame. Ease of work and fitting state, that is, concentricity and stability in which the shaft cores of the fitting portions are aligned are expected.

  The mounting recess of the seat frame is usually manufactured as a cast or resin molded product, and is manufactured so as to be within a predetermined range of dimensions and surface roughness in design. If the conical convex surface and the conical concave receiving surface are perfect conical surfaces, the entire surface closely fits and the coupling strength increases, but it is necessary to increase the processing accuracy, so the seat structure or product as a part As a chair manufacturing cost increases. Since it is common to provide tolerances on the dimensions and surface roughness from the viewpoint of reducing manufacturing costs, this will result in partial adhesion rather than tight fitting on the entire conical surface, and as much as possible. It is inevitable that the strength decreases. If the concave and convex conical surfaces are partly tightly fitted, rattling occurs between the seat mounting part and the mounting recess of the seat frame, causing the seat to wobble with respect to the support column. There is also a risk that the seat body may come off the support column. It is an important inspection item in terms of product safety that the strength of the coupling between the seat frame and the column is high enough to prevent the column or leg from dropping when the seat is lifted, and a decrease in the coupling strength is not preferable.

  As in the case of the cylinder-type telescopic unit and the lifting chair described in Patent Document 2, the seat body frame key engages with the key groove extending in the direction of the cone bus of the cylinder tube, and the seat body mounting portion is attached. There is also a type that prevents the rotation of the seat body with respect to the recess, that is, the rotation of the seat body with respect to the cylinder tube. However, the key must be molded and processed on one part, and the keyway on the other part, which is a cause of the cost increase of the chair. The effect of preventing slipping out cannot be obtained.

JP 2008-99837 A JP 08-336436 A

  Therefore, a coupling structure for coupling a support to which a leg is attached and a seat support for supporting a seat, or a chair provided with such a coupling structure, wherein the support has a top side that is cut off at an upper end thereof and a peripheral side. The seat has a frustoconical shape with a convex conical surface, and the seat receiver has a concave shape complementary to the convex conical surface of the seat mounting portion. And a seat for coupling the support column and the seat frame by fitting the convex conical surface and the concave conical surface. In the receiving structure, due to the manufacturing error that occurs on the concave and convex conical surfaces due to the precision of the mold and the surface finishing, etc., it is not expected that the conical surfaces will be completely in close contact with each other Even in this case, the structure of the support is simple There are problems to be solved in terms of increasing the coupling strength between the mounting portion and the seat receiving the mounting recess.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and without increasing the manufacturing cost, the support post to which the leg is attached and the seat support that supports the seat body are firmly connected, and in the connected state, the support post and the support support. It is to provide a coupling structure that does not rattle or come off between the two, or a chair having such a coupling structure, particularly an office chair.

  In order to solve the above-mentioned problem, the present invention is a structure for combining a column of a chair and a seat that combines a column to which a leg of the chair is attached to a lower end and a seat that supports the seat of the chair, The support column is provided with a seat body mounting portion formed at a top end portion of the conical surface with the apex side being cut off and a peripheral surface facing upward, and the seat support has an inner peripheral surface of the recess formed on the seat. A column receiving portion formed on a concave conical surface that opens downward and complementary to the convex conical surface of the body mounting portion; and the convex conical surface of the seat mounting portion and the column In the coupling structure in which the support column and the seat support are coupled by fitting the concave conical surface of the receiving portion, a window in which a window edge portion appears on the concave conical surface is formed in the support column receiving portion. And a part of the window edge is caused by a load from the seat receiving side. It is characterized that it is with the convex edge portions biting into the conical surface of the mounting portion.

  According to the combined structure of the chair support and the seat support, a window in which the window edge appears on the concave conical surface of the inner surface of the recessed support receiving portion of the seat support is formed. Since this is an edge portion that bites into the convex conical surface due to the load from the seat receiving side, when a load acts on the column receiving portion due to a person sitting on the chair, the edge portion of the window of the column receiving portion is seated. An action of biting into the convex conical surface of the body attaching portion is generated, and the strut receiving portion and the seat attaching portion are strongly pressed against each other at the edge portion of the window, so that the coupling strength between them is increased.

In this structure of the chair strut and seat receiver, the window formed in the strut receiver appears on the concave conical surface in such a manner that the window edge extends in the middle region of the conical surface inclination direction and in the circumferential direction. A plurality of long windows.
The position where the window edge of the window appears in the column receiving part is an intermediate region viewed in the conical surface inclination direction of the concave conical surface, that is, the central region in the conical surface inclination direction or the hem side of the conical surface from the central region. It is a close area, and it is preferable that the area has a height corresponding to the center of gravity of the column receiving portion and the vicinity thereof when viewed in the axial direction.
Moreover, about the long window formed in a support | pillar receiving part, it forms as a several long window which appears in the aspect in which a window edge extends in the circumferential direction, and the hole is not formed seeing in the cone surface inclined direction of the conical surface It is preferable to have a structure in which the upper and lower regions are connected by a region between adjacent long holes.
Accordingly, it is possible to efficiently secure a wide biting area in the column receiving part and increase the degree of coupling while reducing the labor for forming a hole in the column receiving part.

In the combined structure of the chair support and the seat support, the window formed in the support support may be two symmetrical long windows facing in the radial direction of the concave conical surface.
By making the window formed in the column support part into two symmetrical long windows facing the radial direction of the conical surface, the strength of the column support part and the bite of the support column receiving part to the seat mounting part were strengthened The bond strength is divided into two in the circumferential direction and the balance is improved.

In the combined structure of the chair support and the seat support, the seat mounting portion is formed with a circumferential groove extending in the circumferential direction corresponding to the long window in the convex conical surface. In order to prevent the support receiving part from slipping out of the mounting part, the C-ring having two ring arm parts engages with the circumferential groove through the long window in each ring arm part, so that the seat body mounting It can be said that it is applied to the part and the said support | pillar receiving part. In addition, the circumferential groove appears in the window in the assembled state of the seat mounting portion and the column support portion, and the application state of the C ring is provided on the inner surface of each ring arm portion of the C ring. It is preferable to provide an engaging portion that engages with the circumferential groove.
By making the groove formed in the seat mounting portion a circumferential groove, processing for forming the circumferential groove in the seat mounting portion (for example, lathe processing using a cutting tool) is facilitated. In addition, when the retaining C-ring is fitted from the outside of the coupling structure, the two ring arm portions of the C-ring are fitted into the long windows formed in the column receiving portions, respectively, and each ring arm portion is By engaging the provided engaging portion with the circumferential groove formed in the seat mounting portion, each ring arm portion can be pulled out from the seat mounting portion in the mounted state of the C ring. Can prevent movement.
Since the C-ring itself is easy to mount and remove due to its springiness, there is no hindrance to the mounting and disassembly of the seat receiving portion of the seat receiving portion relative to the seat mounting portion of the supporting column.

In this chair strut / seat receiver coupling structure, the strut support part is composed of two sandwich pieces having a central arcuate part and fixed parts at both ends in order to prevent the pillar support part from slipping out of the seat mounting part. A sandwiching metal fitting can be applied to the seat mounting portion and the column receiving portion, and the both clamp pieces are connected to the seat mounting portion through the long windows of the column receiving portions. The fixed portions can be fastened to each other while being in contact with the conical surface.
Applying two clamping pieces from the outside of the column support part, through the long window of the column support part, the central arcuate part abuts against the seat mounting part and clamps, so that the seat mounting part and the column support part Can be securely combined so as not to exit.

Further, in the combined structure of the chair support and the seat support, in order to prevent the support support from coming out of the seat mounting portion, a fixing screw that is screwed into the support support and penetrates the support support. The tip can be brought into contact with the conical surface of the seat mounting portion.
By screwing the fixing screw into the column receiving part and bringing the tip of the fixing screw penetrating the column receiving part into contact with the conical surface of the seat mounting part, the frictional force between the fixing screw and the seat mounting part increases. The coupling between the seat mounting portion and the column receiving portion is strengthened.

Further, in the combined structure of the chair support and the seat support, the support support portion has an inner conical surface that is continuous with the concave conical surface of the support support portion and is exposed to the recess. In this manner, the fitting ring can be insert-molded, and the conical surface inside the fitting ring can be brought into contact with the conical surface of the seat body mounting portion.
By making a part of the inner surface of the column receiving part abutting against the conical surface of the seat mounting part as the conical inner surface of the fitting ring to be insert-molded, the size and surface roughness of the column receiving unit by resin casting Instead, by using a fitting ring in which these dimensions and surface roughness are separately managed, the close fitting of the concave and convex conical surfaces of the seat mounting portion and the fitting ring is enhanced, and the seat mounting portion and the column support As a result, it is difficult for rattling to occur in the coupling with the part, and the situation where the seat is detached from the support can be prevented.

  Furthermore, the present invention includes a leg, a support column to which the leg is attached to the lower end, a seat body, a seat receiver that supports the seat body, and the coupling structure that couples the support column and the seat receiver. It is a chair characterized by being. According to the chair, when a load is applied to the column receiving part due to a person sitting on the chair or the like, the edge portion of the window of the column receiving part is caused to bite into the convex conical surface of the seat body mounting part. The portion and the seat mounting portion are strongly pressed against each other at the edge portion of the window, so that the coupling strength between the two is increased, and it is possible to prevent rattling and slipping between the support column and the seat.

  Since the coupling structure of the column to which the chair leg according to the present invention is attached and the seat support that supports the seat of the chair is configured as described above, the conical surface of the seat mounting part of the column and the column support of the seat support Even if the conical inner surface of the seat is not formed on the complete conical surface due to manufacturing errors, etc., the window edge is formed with respect to the convex conical surface of the seat mounting part by forming the window in the support receiving part of the seat support. As a result, the window edge portion is strongly pressed against each other, and as a result, a strong coupling strength is obtained between the seat mounting portion of the column and the column receiving unit of the seat. Therefore, it is possible to provide a coupling structure that does not cause rattling or pull-out without increasing the manufacturing cost, or a chair provided with such a coupling structure, particularly an office chair.

FIG. 1 is a perspective view showing an example of a legged strut to which a combined structure of a chair strut and a seat support according to the present invention is applied. 2 is a plan view of the legged support shown in FIG. FIG. 3 is a perspective view showing an embodiment of the coupling structure of the chair support and seat according to the present invention. 4 is a cross-sectional view taken along the line AA of the coupling structure shown in FIG. FIG. 1 is a view showing another embodiment of the connecting structure of the chair support and seat according to the present invention. FIG. 6 is a cross-sectional view showing a modified example of the combined structure of the chair support and seat shown in FIG. FIG. 7 is a perspective view showing still another example of a legged strut to which a combined structure of a chair strut and a seat support according to the present invention is applied. FIG. 8 is a perspective view showing another example of a coupling structure of a support column and a seat support applied to the support column with legs shown in FIG. FIG. 9 is a perspective view showing an example of a general office chair. FIG. 10 is a perspective view showing a seat receiving body of the office chair equivalent to the office chair shown in FIG. 9 and its peripheral structure. FIG. 11 is a cross-sectional view showing the seat main body and its peripheral structure of the office chair shown in FIG.

  Hereinafter, an embodiment of a coupling structure for coupling a chair column and a seat support according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view of an embodiment of a coupling structure for coupling a column and a seat according to the present invention viewed from substantially the side, and FIG. 2 is a plan view of the coupling structure shown in FIG. FIG. In the embodiment shown in FIG. 1 and FIG. 2, the seat body and the backrest structure included in the basic structure are removed from the chair and omitted from the illustration, and the seat receiver body 4 provided in the seat receiver and The structure containing the support | pillar 2 and the leg 8 which are provided in the lower side is shown.

  With regard to the embodiment of the coupling structure for coupling the support column and the seat support shown in FIG. 1, the general structure of the chair (office chair) is, for example, a structure equivalent to that shown in FIGS. Good. The chair has a seat body 4 that constitutes the bottom structure of the seat structure as a main component of the seat support that supports the seat body, and the coupling structure 30 couples the support column 2 and the seat body 4. It is a structure to do. As for the legs 8, the center part 8a is attached to the lower end part of the support column 2, and the five leg parts 8b extend radially from the center part 8a at regular intervals in the circumferential direction. A caster 9 is attached to the tip 8c of the part 8a (reference numerals 8b, 8c, 9 are partly attached). Parts and elements having the same functions as those shown in FIGS. 9 to 11 in the column 2 and the legs 8 are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 3 is a view showing the seat main body 4 shown in FIGS. 1 and 2, and is a perspective view seen from obliquely above in a state where the chair is substantially vertically inverted from the normal posture. FIG. 4 is a cross-sectional view taken along the line AA of the seat receiving body shown in FIG. In FIG. 4, the imaginary line indicates that the seat mounting portion 31 provided at the upper end of the support column 2 is fitted to the support receiving portion 42 provided in the seat receiving body 4 on the seat body side, and the lower end portion of the backrest pipe. Is drawn in a state of being fitted in the groove.

  As shown in FIG. 4, the seat mounting portion 31 provided at the upper end portion of the column 2 of the chair 1 has a conical surface whose top surface is cut off and whose peripheral surface is convex upward (downward in FIG. 4). 32 is formed. In the fitted state of the seat body mounting portion 31 and the column receiving portion 42, the center axis CL of the cone having the conical surface 32 coincides with the center axis of the column 2. Further, the apex angle α of the conical surface 32, that is, the prospective angle of the two busbars that are most open to each other, is a slight angle such as 2.9 ° as shown in FIG. Therefore, the seat attachment part 31 is formed in a truncated cone having a conical surface 32 slightly narrowed upward.

  As shown in FIGS. 3 and 4, the seat receiving body 4 has a substrate portion 40 having a rectangular outer shape as a whole. The upper surface 41 of the substrate portion 40 is a flat surface, and a flat bottom surface of a seat receiving structure (a shell structure in which an operation lever as shown in FIG. 8 is incorporated) can come into contact. In a state in which the seat receiving body 4 is fitted to the seat body mounting portion 31 of the support column 2, the upper surface 41 becomes a horizontal plane with respect to the support column 2 whose central axis CL is vertical. As a main structure, the seat receiving body 4 includes a cylindrical column receiving portion 42 that is integrally formed so as to protrude downward from the base plate portion 40 at the approximate center. Further, the seat receiving body 4 is formed in a form in which a portion of the board portion 40 adjacent to the column receiving portion 42 is bent and deformed downward so that a part thereof is integrated with the column receiving portion 42. The backrest pipe insertion groove 43 is provided. Further, the seat receiving body 4 is formed with mounting holes 44 at the four corners of the base plate portion 40 through which fasteners such as bolts and blind rivets 28 are inserted for mounting to the seat receiving structure. The seat main body 4 is fixed as a bottom structure of the seat receiving structure by a fixing tool inserted into the mounting hole 44 in a state where the seat receiving structure is applied to the upper surface 41 of the substrate portion 40.

  The column receiving part 42 provided in the seat receiving main body 4 has a substantially cylindrical structure, and a column receiving hole penetrating vertically is formed inside, ie, a fitting hole 45 serving as a recess. . The inner peripheral surface of the fitting hole 45 is formed as a concave conical surface 46 that opens downward complementary to the convex conical surface 32 of the seat mounting portion 31 (vertical angle is 2.9 °). Yes. The central axis corresponding to the conical surface 46 coincides with the central axis CL of the conical surface 32 of the seat mounting part 31 in the fitted state and is perpendicular to the upper surface 41. The outer peripheral surface of the column receiving portion 42 is formed in a convex conical surface 47 that is constricted toward the lower side, opposite to the conical surface 46, in view of manufacturing requirements in consideration of removal from the mold. . Therefore, the cylindrical wall between the concave conical surface 46 and the convex conical surface 47 of the column receiving part 42 has a substantially cylindrical structure with the wall thickness increasing toward the upper side.

  The support column 42 is formed with windows 48 and 48 penetrating the cylindrical wall from the concave conical surface 46 which is the inner surface to the convex conical surface 47 which is the outer surface. The windows 48, 48 are a plurality of long windows formed in an intermediate region in the height direction of the column receiving portion 42 and extending in the circumferential direction. In this embodiment, the central axis of the conical surface 46 is formed by casting. The two windows are symmetrically formed so as to be opposed to each other in the radial direction of the concave conical surface 46 so as to be cut in parallel with each other. Each window 48 includes two fan-shaped surfaces 50 and 50 (only one is denoted by a reference numeral) which are vertically opposed and parallel to each other on the cylindrical wall, as shown in the front window 48 of FIG. It is defined by two trapezoidal surfaces 51, 51 formed on each side of the direction. In this embodiment, the two trapezoidal surfaces 51, 51 are in one common plane. As for the windows 48, 48, the window contours in the concave conical surface 26 are shown as window edges 52, 52 that appear in the form extending in the circumferential direction in the intermediate region of the conical surface inclination direction.

  The backrest pipe insertion groove 43 is formed with a single groove 55 that crosses linearly so as to pass from one side in the width direction of the substrate part 40 to the other side. As shown by an imaginary line in FIG. 4, the groove 55 is fitted with a lower end portion 5b having a circular cross section connecting the lower ends of the backrest pipes 5a and 5a extending from the upper side to the upper side of the seat receiving body 4 more than the width. Is done. The backrest pipes 5a and 5a can be configured such that the backrest angle γ can be changed when the lower end portion 5b rotates in the groove 55. The mounting holes 44 at the four corners are used as insertion holes for fasteners such as bolts or blind rivets. The bolts or blind rivets are inserted into the mounting holes 44 from below, and the bolts are screwed into the seat body or the blind rivets are fastened. Thus, the receiving body 4 can be fixed to the seat. In FIG. 3, a blind rivet 28 is shown as an example of attaching the fixing tool to one mounting hole 44.

  In the coupling structure 30, by fitting the convex conical surface 32 of the seat mounting portion 31 on the support column 2 side and the concave conical surface 46 of the support column receiving portion 42 on the seat receiving body 4 side, The support column 2 and the seat receiving body 4 are coupled. A part of the window edge 52, in particular, the window edge 52a (see FIG. 4) extending in the circumferential direction on the upper side is a convex shape of the seat mounting portion 31 when pressed downward by a load from the seat receiving body 4 side. It is an edge portion that bites into the downwardly expanding conical surface 32. Due to the biting action of the window edge portion 52, the seat receiving body 4 is firmly coupled to the seat body mounting portion 31.

  As in this embodiment, the number of windows and each surface are not necessarily two windows 48, 48, and each surface may be symmetrical, parallel, or flush. For example, the window may be formed as a window in which three or four windows are arranged in the circumferential direction. The fan-shaped surfaces 50 and 50 may be formed so as to open outward rather than in parallel to each other, and the trapezoidal surfaces 51 and 51 may also be inclined so as to face each other, not flush with each other. However, if the fitting state with a good balance with the support | pillar 2 is considered, what is shown in an Example is preferable. In addition, the thing of the Example of illustration has a preferable shape and structure also when applying the C ring mentioned later.

  FIG. 5 is a perspective view showing another embodiment of the combined structure of the chair support and the seat support according to the present invention. By using a C-ring 60 described later, the seat support body 4 of the seat support and the support seat. This is intended to prevent inadvertent disconnection from the body mounting portion 31. 5A is an exploded perspective view of the coupling structure, FIG. 5B is a perspective view of the coupling structure after assembly, and FIG. 5C is a cross-sectional view taken along line BB in FIG. 5B. In the coupling structure 30 of the previous embodiment, the seat receiving body 4 is coupled to the seat mounting portion 31 by the biting action of the window edge 52, but when the chair 1 is lifted by gripping only the seat body side, 2 and the weight of the leg 8 may act to loosen the coupling by the coupling structure 30. Even in such a case, a device may be required to prevent the seat body 4 from falling off the seat body 4.

  In the coupling structure 30 a shown in FIG. 5, a C-ring 60 is applied between the seat mounting portion 31 and the column receiving portion 42 in order to prevent the column receiving portion 42 from coming out of the seat mounting portion 31. . In order to apply the C-ring 60, a single circumferential groove extending in the circumferential direction corresponding to the windows 48, 48 formed in the seat receiving body 4 in the convex conical surface 32 is formed on the seat mounting portion 31 of the support column 2. 35 is formed. The circumferential groove 35 is formed in the seat body mounting portion 31 so as to appear at the center of the height of the windows 48 and 48 in a state where the seat body mounting portion 31 and the column receiving portion 42 are assembled. Although it is sufficient that the circumferential groove 35 is formed only in the corresponding portion so as to appear in the windows 48, 48, it is preferable to form a circumferential groove in order to facilitate manufacturing by cutting.

  As shown in FIG. 5, the C-ring 60 has a central base 61 that is bent in a substantially U-shape, and two bulges that extend in a circular arc from both ends of the central base 61 in the same direction in a convex manner on both sides. Two ring arm portions 62, 62 are provided. The central base 61 is used for gripping the C-ring 60 and performing an attaching operation to the seat support. The central base portion 61 and the two ring arm portions 62 and 62 have a spring property in the spreading direction, and cooperate to surround the conical surface 32 of the seat mounting portion 31 and to hold the conical surface 32 by the spring property. Can have. An engagement portion 63 is formed on the inner surface side of each ring arm portion 62 to engage with the circumferential groove 35 and maintain the engagement position. The engaging portion 63 is formed as a hemispherical protrusion in this example. As shown by the arrow in FIG. 5A, the C ring 60 is located on the outer side of the column receiving portion 42 with respect to the seat mounting portion 31 of the column 2 in the assembled state and the column receiving portion 42 of the seat receiving body 4. Applied along the windows 48, 48 from the side. That is, the C ring 60 is slightly widened by bending the ring arm portions 62, 62, and the engaging portions 63, 63 are slid along the circumferential groove 35 in a state of being hooked on the circumferential groove 35. It gradually deeply engages with the receiving portion 42. The engaging portions 63 and 63 are engaged with the circumferential groove 35 by the spring restoring properties of the ring arm portions 62 and 62. When a plurality of engaging portions 63 are provided in each ring arm portion 62, the engaging portion 63 is snap-engaged with the circumferential groove 35 by the spring restoring property of the ring arm portions 62, 62 to prevent disengagement. be able to.

  The two ring arm portions 62, 62 of the C-ring 60 are not only engaged by engaging the engaging portions 63, 63 in the circumferential groove 35 of the seat mounting portion 31, but are also fitted into the windows 48, 48, respectively. The side ends 64 and 64 of the ring arm portions 62 are engaged with the fan-shaped surfaces 50 and 50 of the windows 48 in a contact state. The engagement between the seat mounting portion 31 and the column receiving portion 42 of the C ring 60 prevents relative displacement in the height direction between the seat mounting portion 31 and the column receiving portion 42. Maintenance is achieved, and it is possible to prevent the column receiving part 42 from coming out of the seat mounting part 31. Further, the two ring arm portions 62, 62 of the C ring 60 hold the conical surface 32 of the seat mounting portion 31 in the radial direction by their spring property, so that the C ring 60 is not prepared from the support column receiving portion 42. There is no risk of disengagement. When it is necessary to separate the seat receiving body 4 from the column 2, the application operation of the C ring 60 is followed in reverse to remove the C ring 60 from the column receiving part 42. That is, the operation of pulling out the C-ring 60 from the windows 48 and 48 by grasping the central base 61 widens the engaging portions 63 and 63 against the spring properties of the ring arm portions 62 and 62, and in the circumferential groove 35. The coupling structure 30 can be released by removing the C-ring 60 from the support post 42.

  As for the circumferential groove 35, as shown in the above-mentioned embodiment, the cross section is preferably an arc shape, but the shape is not limited to this. Any groove shape may be used as long as the engaging portions 63 and 63 of the C-ring 60 pass through and are arranged. In addition, when the engaging portions 63 are provided one by one in the ring arm portions 62 and 62, they may be provided in the center in the longitudinal direction, but the C ring 60 is prevented from coming out of the windows 48 and 48 in the returning direction. Therefore, it is preferable to provide at a position slightly farther from the center base 61 than the center position in the longitudinal direction. Furthermore, the engaging part 63 may be provided at a plurality of (preferably two) positions sandwiching the center along the longitudinal direction of each ring arm part 62. Due to the structure of the circumferential groove 35 and the window 48, the ring arm portions 62, 62 of the C-ring 60 are easily accommodated in the windows 48, 48, and the engaging portions 63, 63 of the ring arm portions 62, 62 are surrounded in the accommodated state. Engaging in the groove 35, the C-ring 60 itself can be applied stably so as not to blind. Note that when the seat receiving body 4 is made of resin, the C-ring contributes to improving the strength of the seat receiving body 4 when attached to the seat receiving body 4.

  FIG. 6 shows a cross-sectional view of a modified example of the combined structure of the chair support and seat shown in FIG. In the coupling structures 30b and 30c shown in FIG. 6, the same components as those used in the coupling structure 30a shown in FIG. The coupling structure 30b shown in FIG. 6 (a) is a structure in which the column receiving part 42 is fixed to the seat mounting part 31 of the column 2 with screws. A screw hole 72 is formed in a part of the cylindrical column receiving part 42 (lower part in this example), a fixing screw 70 is screwed into the screw hole 72, and a tip 71 of the fixing screw 70 connects the column receiving part 42. It penetrates and is pressed against the conical surface 32 of the seat mounting part 31. As the fixing screw 70, a hexagon socket head cap screw is used, but various other bolts can be used. The right side of the figure shows a state before the fixing screw 70 is screwed into the screw hole 72, and the left side of the figure shows a state where the fixing screw 70 is screwed into the screw hole 72 and the tip 71 is pressed against the conical surface 32. As the tip 71 comes into contact with the conical surface 32, the fastening force between the fixing screw 70 and the seat mounting portion 31 is increased, and the column receiving portion 42 is fixed to the column 31, and from the column receiving portion 42 of the column 31. Is prevented from being pulled out. With regard to the fixing screw 70 and the screw hole 72, at least one set can provide a retaining effect. However, from the viewpoint of the balance of the fixing force, the two directions or the central axis CL facing each other in the diametrical direction as shown in the figure. It is preferable to screw in and fix from three directions at equal intervals around 120 degrees.

A coupling structure 30 c shown in FIG. 6B is a structure in which a fitting ring 75 is embedded in the column receiving part 42. The fitting ring 75 is a conical cylindrical metal ring manufactured by metal processing. Instead of the dimensions and surface roughness of the column receiving portion 42 by resin casting, the dimensions and surface roughness of the fitting ring 75 are managed in advance with high accuracy at the time of manufacture. The fitting ring 75 is embedded in the support column 42 by insert molding when the support column 42 is resin-molded. At the time of insert molding, the fitting ring 75 is embedded so that the inner conical surface 76 thereof is flush with the concave conical surface 46 of the column receiving portion 42 and is exposed to the recess of the column receiving portion 42. When the support body part 31 of the support column is combined with the support part 42 in which the fitting ring 75 is insert-molded, the conical surface 76 of the engagement ring 75 and the conical surface 32 of the seat support part 31 have a high degree of adhesion. And a fitting strength with the conical surface 32 of the seat mounting part 31 can be ensured to a certain level or more. Therefore, it is difficult for rattling to occur in the coupling between the seat body attaching portion 31 and the column receiving portion 42, and the situation where the seat body is detached from the column can be prevented.

  In the above embodiment, the coupling structures 30 and 30a to 30c of the support column 2 to which the chair leg 8 is attached and the seat support 4 that supports the chair seat 7 have been described. However, the present invention departs from the technical idea. Various modifications and additions can be made without departing from the scope, and the present invention is not limited to the above embodiments. In addition, since it is a trivial technical matter to construct a chair that does not have a structure such as a backrest or an armrest attached to the seat body, a chair having such a coupling structure can also be implemented.

  FIG. 7 is a perspective view showing still another example of a legged strut to which a coupling structure of a chair strut and a seat support according to the present invention is applied. The example shown in FIG. 7 is a support column with legs applied to a chair having a simple structure, and the seat receiving body 4a does not include the back pipe insertion groove 43 in the seat receiving body 4 shown in FIGS. Structure. Therefore, the board | substrate part 40a with which the seat receiving main body 4a is equipped has a substantially square shape seeing with a top view. Since the other structure is the same as that of the seat receiving body 4 shown in FIGS. 1 to 4, the same reference numerals as those in FIG. To do.

  FIG. 8 is a view showing another example of the coupling structure of the support column 2 and the seat receiving body 4a shown in FIG. FIG. 8A is a perspective view showing an example of a clamp fitting used in this coupling structure, and FIG. 8B is a perspective view in the middle of coupling the column and the seat support using this clamp fixture, FIG. FIG. 4 is a perspective view showing a state in which the work of joining proceeds from (b) and the support and the seat are joined. The coupling structure 30d of this example is a structure that uses a clamping fitting 80 as shown in FIG. 8A in place of the C-ring shown in FIG. This is applied to the long windows 48 and 48, and the support body 2 and the seat receiving body 4a are joined by sandwiching and tightening the seat mounting portion 31 from both sides. The sandwiching bracket 80 is composed of two sandwiching pieces for sandwiching the seat mounting portion 31 and the column receiving portion 42, and uses a pair of sandwiching pieces 81, 81 formed in the same shape as shown in the figure. Is preferred. Each sandwiching piece 81 includes a central arc-shaped portion 82, flat portions 83 and 83 on both sides thereof, and fixed portions 84 and 84 on the outside thereof, and a metal plate having an elongated uniform width W. It is a metal piece of an integral structure manufactured by bending. Strictly speaking, the arc-shaped portion 82 may be processed so as to have a partial conical surface corresponding to the conical surface 32, but it has a simple partial cylindrical surface in consideration of deformation during tightening. Good. Each fixed portion 84 is formed with a hole 85 through which a bolt 86 used for fastening is passed. In addition, the seat receiving body 4a shows a state where it is attached as a bottom structure in a seat receiving structure in which an operation lever is incorporated and attached to a seat body of a chair.

  As shown in FIG. 8B, the clamp fitting 80 is applied in relation to the windows 48 and 48 of the column receiving portion 42. Since the width W of each sandwiching piece 81 is determined by the dimension of the height H (FIG. 5A) of the window 48 of the column receiving portion 42, each sandwiching piece 81 is wider than the window 48. Fit so that W just fits the height H of the window 48. When each sandwiching piece 81 is applied to the column receiving part 42 from the outside, the arc-shaped portion 82 is fitted between the fan-shaped surfaces 50 and 50 of the window 48 formed in the column receiving part 42, The flat portions 83, 83 extend along the trapezoidal surfaces 51, 51 of the windows 48, 48, and the fixed portions 84, 84 at both ends are located outside the column receiving portion 42 outside the window 48. Since each sandwiching piece 81 faces the other sandwiching piece 81 at the fixing portions 84, 84 at both ends, the bolts 86 are passed through holes 85, 85 that are aligned with each other at the fixing portions 84, 84 facing each other. The clamping pieces 81 and 81 are fastened by screwing the nuts 87 to the bolts 86. At this time, the arc-shaped portions 82 and 82 fitted into the windows 48 and 48 sandwich the seat mounting portion 31 of the support column 2 and are strongly pressed against the conical surface 32 thereof. That is, the sandwiching pieces 81, 81 are sandwiched between the arcuate portions 82, 82 in contact with the conical surface 32 of the seat mounting portion 31 through the windows 48, 48 of the column receiving portion 42, and the fixing portions 84, 81. 84 are fastened together. The clamped metal fitting 80 is positioned with respect to the column receiving portion 42 in such a manner that the arc-shaped portion 82 and the flat portion 83 are directly fitted in the windows 48, 48, and indirectly, the arc-shaped portion 81. However, since the curved surfaces abut against the seat mounting portion 31, it is restricted, and the column 2 and the seat receiving body 4 a are coupled via the clamping metal fitting 80, and the column receiving unit 42 and the seat mounting are attached. Both can be reliably combined so that the part 31 does not come out.

DESCRIPTION OF SYMBOLS 1 Office chair 2 Support | pillar 2a Cover body 3 Gas spring 3a Main body part 3b Rod 3c Operation button 4, 4a Seat receiving body 5 Backrest 5a Backrest pipe 5b Lower end part 6 Seat shell 7 Seat body 8 Leg 8 8a Center part 8b Leg Portion 8c tip portion 9 caster 10 groove 11 longitudinal groove 12 operation lever 13 round bar 13a action portion 14 pivot 15 mounting bolt 16 mounting hole 18 gas cradle 18a upper surface 19 through port 20 through port 21 handle 22 curved portion 23 frame-shaped rib 25 Rotating support portion 26 Flat surface 28 Blind rivet 30, 30a, 30b, 30c, 30d Coupling structure 31 Seat mounting portion 32 Conical surface 35 Circumferential groove 40 Substrate portion 41 Top surface 42 Supporting column receiving portion 43 Backrest pipe insertion groove portion 44 Installation Hole 45 fitting hole 46 concave conical surface 47 convex conical surface 48, 48 window 50, 50 Shaped surface 51, 51 Trapezoidal surface 52, 52, 52a Window edge portion 55 Groove 60 C ring 61 Central base portion 62, 62 Ring arm portion 63 Engagement portion 64, 64 Side end 70 Fixing screw 71 Tip 72 Screw hole 75 Fitting ring 76 Conical surface 80 Clamping bracket 81 Clamping piece 82 Arc-shaped part 83 Flat part 84 Fixed part 85 Hole 86 Bolt 87 Nut CL Center axis α Vertical angle γ Backrest angle W Width of clamping piece 81 H Height of window 48

Claims (9)

A coupling structure that couples a column to which a leg of a chair is attached to a lower end and a seat support that supports a seat body of the chair,
The support column is provided with a seat attachment part formed on a convex conical surface with the peripheral side facing upward and the top side being cut off at the upper end.
The seat support includes a column support portion formed on a concave conical surface that is opened below the inner peripheral surface of the recess complementary to the convex conical surface of the seat mounting portion.
In the coupling structure for coupling the column and the seat receiver by fitting the convex conical surface of the seat body mounting portion and the concave cone surface of the column support portion,
A window in which a window edge portion appears on the concave conical surface is formed in the column receiving portion, and a part of the window edge portion is formed in the convex shape of the seat body mounting portion by a load from the seat receiving side. A combined structure of a chair support and a seat support, characterized by an edge portion that bites into the conical surface.   The said window formed in the said support | pillar receiving part is a some long window which appears in the aspect which the said window edge part is a cone surface inclination direction intermediate area and the circumferential direction in the said concave conical surface. Item 2. A structure for combining a chair support and a seat support according to Item 1.   3. The chair support and the seat support according to claim 2, wherein the long window formed in the support receiving part is two symmetrical long windows facing in the radial direction of the concave conical surface. 4. Bond structure.   The seat mounting portion is formed with a circumferential groove extending in the circumferential direction corresponding to the long window on the convex conical surface to prevent the support receiving portion from slipping out of the seat mounting portion. Therefore, a C-ring having two ring arm portions is applied to the seat body mounting portion and the support column receiving portion in such a manner that each ring arm portion engages with the circumferential groove through the long window. The combined structure of a chair post and a seat support according to claim 3.   The circumferential groove appears in the window in the assembled state of the seat body attaching portion and the column support portion, and the inner surface of each ring arm portion of the C ring is in the applied state of the C ring. The coupling structure for a chair column and seat according to claim 4, wherein an engaging portion is provided to engage with the circumferential groove. In order to prevent the support receiving part from slipping out from the seat mounting part, a clamp fitting made of two clamping pieces having a central arcuate part and fixed parts at both ends includes the seat mounting part and the support post. The both clamping pieces are arranged in such a manner that the respective arcuate portions are in contact with the conical surface of the seat mounting portion through the long windows of the support columns. The joint structure of a chair post and a seat support according to claim 3, wherein the structure is fastened to each other. In order to prevent the column receiving part from coming out of the seat mounting part, the tip of a fixing screw screwed into the column receiving part and passing through the column receiving part abuts on the conical surface of the seat mounting part. The joint structure of a chair post and a seat support according to any one of claims 1 to 6, wherein the structure is combined. In the aspect in which the inner conical surface is continuously flush with the concave conical surface of the column receiving part and exposed to the recess, the fitting ring is insert-molded in the column supporting part, The joint of the chair support and the seat support according to any one of claims 1 to 7, wherein an inner conical surface of the fitting ring is in contact with the conical surface of the seat mounting portion. Construction.   The leg, a support to which the leg is attached to a lower end, a seat, a seat support that supports the seat, and the support and the seat support are coupled to each other. A chair comprising the coupling structure.

Images