Chair upholstery construction

Abstract

This invention provides a chair upholstery structure that allows the upholstery to be applied to the body contact surface of the chair with appropriate tension, and enables the upholstery work to be performed in an extremely simple and efficient manner. [Solution] After the body contact surface forming upholstery 22, 52 is hooked onto the contact surface forming frame 20, 50, the fitting members 21, 51 are fitted into the separated portions 25, 55 of the contact surface forming frame 20, 50, causing the contact surface forming frame 20, 50 to expand in the direction of tension of the body contact surface forming upholstery 22, 52, thereby applying tension to the upholstery.

Description

Technical Field

[0001] The present invention relates to a structure for stretching a sheet-like upholstery on a chair where the body comes into contact.

Background Art

[0002] In a chair where a sheet-like upholstery is stretched on a body-contact part, as a method for stretching the upholstery, an elongated plate-like locking member is attached to the edge of the upholstery, and the edge is folded back together with the locking member and fitted into a groove formed in a frame for locking. This method is known (Patent Documents 1 to 3 below).

[0003] Specifically explaining this method of stretching the upholstery using the backrest of a chair as an example, first, after fitting the locking member of the upholstery into the groove located at the upper part of the backrest frame, the lower side of the upholstery is manually pulled downward with some force or pulled downward by a mechanical operation using a robot or the like and fitted into the groove located at the lower part of the backrest frame. <​​​​​​​​​​​​​​​​​​​​​​However, with the conventional methods of installing upholstery as described above, applying proper tension to the upholstery requires considerable downward force, placing a significant burden on the worker when done manually. Furthermore, using robots or other equipment inevitably incurs equipment installation costs, resulting in a substantial financial burden. In addition, when done manually, there are limitations to the downward force that can be applied, sometimes making it impossible to apply appropriate tension to the upholstery. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Therefore, the present invention aims to provide a chair upholstery structure that can stretch contact surface forming upholstery onto a contact surface forming frame with appropriate tension, reduce the labor involved in the upholstery work, and enable efficient upholstery work. [Means for solving the problem]

[0007] To solve the aforementioned problems, the present invention provides a chair upholstery structure in which a sheet-like upholstery is stretched over a part of the chair that comes into contact with the body, comprising a support base provided at the part of the chair that comes into contact with the body, and an upholstery stretching mechanism attached to the support base, wherein the upholstery stretching mechanism is composed of a contact surface forming frame body formed as an annular frame of an elastic member and having separated portions formed at one or more locations thereof, an insertion member fitted into the separated portion of the contact surface forming frame body to expand the contact surface forming frame body, and an elastic body contact surface forming upholstery having its periphery hooked onto the contact surface forming frame body, wherein after the body contact surface forming upholstery is hooked onto the contact surface forming frame body, the insertion member is fitted into the separated portion of the contact surface forming frame body, causing the contact surface forming frame body to expand in the direction of tension of the body contact surface forming upholstery and to apply tension to the upholstery. In this context, "ring-shaped" refers to a shape in which the beginning and end are roughly connected, enclosing the central part, and includes not only circular shapes but also rectangular and other shapes.

[0008] Furthermore, it is desirable that the contact surface forming frame in the present invention be detachably attached to the support base by engaging a locking portion or a locked portion provided on the support base with a locking portion or a locked portion provided on the support base. [Effects of the Invention]

[0009] This invention allows for the application of contact surface forming upholstery to a contact surface forming frame while applying appropriate tension. Furthermore, it allows for easy adjustment of the location and strength of the tension applied to the body contact surface forming upholstery. In addition, this invention reduces the labor involved in the application process and enables efficient application of the upholstery.

[0010] Furthermore, according to the invention described in claim 2, when it is necessary to replace the upholstery that forms the body contact surface, the replacement work can be easily carried out. [Brief explanation of the drawing]

[0011] [Figure 1] A perspective view of a chair. [Figure 2] Decomposed perspective view of the seat. [Figure 3] Decomposed perspective view of the backrest. [Figure 4] A diagram showing the procedure for attaching the seat-forming upholstery to the seat-forming frame. [Figure 5] Plan view of the seat in another embodiment. [Modes for carrying out the invention]

[0012] The following describes embodiments of the chair upholstery structure according to the present invention with reference to the drawings. Incidentally, the chair upholstery structure according to the present invention is applied to chairs in which sheet-like upholstery is stretched over the parts that come into contact with the body. In this embodiment, however, the parts that come into contact with the body are assumed to be the seat, which comes into contact with the seated person's buttocks, and the backrest, which comes into contact with the seated person's back. However, if upholstery is used to provide body contact surfaces in other areas, such as the armrests of the chair, the back of the seated person's head, or calves, then those areas can be considered as body contact areas in the present invention. Figure 1 is a perspective view of the chair, Figure 2 is an exploded perspective view of the seat, Figure 3 is an exploded perspective view of the backrest, and Figure 4 is a diagram showing the procedure for stretching the seat-forming upholstery over the seat-forming frame. In this description of the embodiment, "front" refers to the area in front of a person sitting normally in a chair, "rear" refers to the area behind a person sitting normally in a chair, and "right" and "left" refer to the right and left sides of a person sitting normally in a chair.

[0013] The chair of this embodiment comprises legs (not shown), a seat 1 positioned above the legs, a backrest 2 that rises upward from the rear of the seat 1, and a pair of armrests 3, 3 provided on the left and right sides of the seat 1. However, the present invention does not require legs or armrests 3, 3 as essential components and can be applied to chairs that do not have these.

[0014] The upholstery structure of the chair in this embodiment is generally composed of support bases 1A and 2A provided on the seat 1 and backrest 2, respectively, which are the body contact points, and upholstery mechanisms 1B and 2B attached to the support bases 1A and 2A.

[0015] The seat 1 is composed of a seat support shell 1A as a support base and a fabric tensioning mechanism 1B that is detachably attached to the upper side of the seat support shell 1A. The seat support shell 1A is a member provided above the legs and, as shown in Figure 2, is formed by a peripheral edge 10 that is formed in an annular shape with a roughly square shape in plan view and a bottom 11 located below the peripheral edge 10. That is, the seat support shell 1A has an annular peripheral edge 10 as its overall shape and is formed in a roughly box shape that bulges downward from the peripheral edge 10. The peripheral edge 10 of the seat support shell 1A is a roughly square in plan view formed by a pair of left and right rods 10a, 10b and a pair of front and rear rods 10c, 10d in a continuous manner, but the rear end is slightly arc-shaped and the left and right corners of the front end are also arc-shaped, so the whole thing is a slightly rounded annular square. Furthermore, the front end of the peripheral edge 10 of the seating shell 1A is slightly inclined downward toward the front. In addition, the peripheral edge 10 of the seating shell 1A has upright walls 10e and 10f erected on the outer edge and slightly inward from the outer edge (inner edge), respectively, and these upright walls 10e and 10f form a frame fitting groove 12 into which the seating surface forming frame 20, which will be described later, is fitted. In addition, multiple locking parts 13, 13... (eight in this embodiment) are provided within this fitting groove 12 for detachably attaching the seating surface forming frame 20.

[0016] The upholstery tensioning mechanism 1B provided on the seat 1 is generally composed of a seat surface forming frame 20 as a contact surface forming frame, a fitting member 21 that fits into the seat surface forming frame 20, and a seat surface forming upholstery 22 that locks onto the seat surface forming frame 20 as a contact surface forming upholstery.

[0017] The seat-forming frame 20 is formed as an annular frame from a synthetic resin member. That is, it is formed in a frame shape surrounding the central space with rod-shaped members made of synthetic resin, and is sized to fit within the peripheral edge 10 of the seat-support shell 1A, specifically within the frame fitting groove 12 of the peripheral edge 10. In other words, the seat-forming frame 20, like the peripheral edge 10 of the seat-support shell 1A, is approximately square in plan view, formed by a pair of left and right rods 20a, 20b and a pair of front and rear rods 20c, 20d in a continuous manner, and its shape in plan view is approximately the same as the peripheral edge 10 of the seat-support shell 1A. However, in the state before the seat-forming upholstery 22 is attached, the seat-forming frame 20 is divided into two parts and separated at the left and right positions from its rear end. Specifically, the seating frame is divided into two roughly U-shaped members, one at the front and one at the rear. The left and right end faces of the front seating frame 20A and the left and right end faces of the rear seating frame 20B are spaced apart from each other. The end face of the rear seating frame 20B has forward-projecting rectangular parallelepiped insertion protrusions 23, 23, and the end face of the front seating frame 20A has insertion recesses 24, 24 into which the insertion protrusions 23, 23 are inserted. The spaced-apart portions (fitting portions) 25, 25 where the fitting member 21 is fitted are located. Furthermore, as shown in Figure 2, a narrow locking groove 26 is provided around the outer circumference (side portion) of the seating frame 20. This locking groove 26 is where the periphery of the seat-forming upholstery 22, which will be described later, is secured. In addition, the lower end of the seat-forming frame 20 is provided with multiple locking parts (eight in this embodiment) for detachably attaching the seat-forming frame 20 to the seat-supporting shell 1A, although these are not shown in the figures. Furthermore, a cushion support part 28 is provided on the inner part of the rod 20c located in front of the seat-forming frame 20, on which a cushion member 27 molded from urethane is placed. Incidentally, although the insertion projection 23 provided on the rear seat-forming frame 20B is shown to be rectangular in shape above, the shape can be freely selected as long as the insertion projection can be inserted into the insertion recess.In addition, in the above description, the insertion convex portion 23 is provided on the rear seat surface forming frame body 20B, and the insertion concave portion 24 is provided on the front seat surface forming frame body 20A. However, this can be reversed, that is, the insertion convex portion can be provided on the front seat surface forming frame body 20A, and the insertion concave portion 24 can be provided on the rear seat surface forming frame body 20B. Further, concave portions may be provided on both end surfaces of the front seat surface forming frame body 20A and the rear seat surface forming frame body 20B, and a rod-shaped member may be inserted into one side thereof to form an insertion convex portion, and the insertion convex portion may be inserted into the concave portion on the other side. In short, it is only necessary that an insertion convex portion protruding from one end surface and an insertion concave portion for receiving the insertion convex portion are formed on the other end surface. Further, in the above description, an example in which the locking groove 26 of the seat surface forming frame body 20 is provided around is shown, but the locking groove may be intermittently provided at intervals instead of being continuously provided around.

[0018] The fitting member 21 is a member to be fitted into the separation portion 25 of the seat surface forming frame body 20, that is, the separation portion 25 between the end surface of the front seat surface forming frame body 20A and the end surface of the rear seat surface forming frame body 20B, and is formed in a substantially rectangular parallelepiped block shape. And a locking groove 30 for hooking the periphery of the seat surface forming ground 22 is formed on one end side. This locking groove 30 is configured to be continuous with the locking groove 26 of the seat surface forming frame body 20 in a state where the fitting member 21 is fitted to the seat surface forming frame body 20. Further, a convex portion hooking piece 31 formed in an L shape is provided at the lower end portion of the fitting member 21. This convex portion hooking piece 31 is to be hooked on the insertion convex portion 23 of the seat surface forming frame body 20 in a state where the fitting member 21 is fitted to the seat surface forming frame body 20.

[0019] The seat surface forming ground 22 is made of a material having an elastic force, that is, a stretchable sheet-like material. In this embodiment, a mesh material is adopted. And a hooking piece 35 for hooking the seat surface forming ground 22 to the seat surface forming frame body 20 is fixed to the periphery of the seat surface forming ground 22. This hooking piece 35 is formed of a narrow strip-shaped plate material as shown in FIG. 2, and does not go around the entire peripheral portion of the seat surface forming ground 22, but is intermittently divided at some places. Specifically, in this embodiment, it is divided at a total of 8 places.

[0020] The backrest 2 is composed of a back frame 2A as a support base and a stretching mechanism 2B for stretching the fabric, which is detachably attached to the front side of the back frame 2A. Among these, the back frame 2A is provided so as to stand up from the rear end portion of the seat surface forming frame body 20 of the seat 1, and is formed by a peripheral portion 40 formed in an annular shape that is U-shaped in side view and vertically long rectangular in front view, and a seat attachment portion 41 provided below the peripheral portion 40. Although not shown in the figure, the back frame 2A is tiltably attached to the seat receiving shell 1A of the seat 1 via a back frame attachment member at the seat attachment portion 41. The peripheral portion 40 of the back frame 2A has standing walls 40a and 40b erected respectively at the outer peripheral edge and a position slightly inside from the outer peripheral edge (inner peripheral edge), and a frame fitting groove 42 for fitting a back surface forming frame body 50 described later is formed by these standing walls 40a and 40b. Further, a plurality (six locations in this embodiment) of locking portions 43, 43... for detachably attaching the back surface forming frame body 50 are provided in the frame fitting groove 42.

[0021] The stretching mechanism 2B provided on the backrest 2 is generally composed of a back surface forming frame body 50 as a contact surface forming frame body, a fitting member 51 fitted to the back surface forming frame body 50, and a back surface forming fabric 52 as a contact surface forming fabric locked to the back surface forming frame body 50.

[0022] The back frame 50 is formed as a vertically elongated rectangular annular frame from a synthetic resin member with elasticity. That is, it is formed in a frame shape that surrounds the central space with rod-shaped members made of synthetic resin, and is sized to fit within the peripheral edge 40 of the back frame 1B, specifically within the frame fitting groove 42 of the peripheral edge 40. In other words, the back frame 50, like the peripheral edge 40 of the back frame 1B, is a rectangle in plan view formed by a pair of left and right rods 50a, 50b and a pair of upper and lower rods 50c, 50d in a continuous manner, and its shape in plan view is substantially the same as the peripheral edge 40 of the back frame 1B. However, in the state before the back upholstery 52 is attached, the back frame 50 is divided into two parts and separated at approximately the center in the vertical direction. Specifically, it is divided into two roughly U-shaped members, an upper and a lower section, with the left and right end faces of the upper back-forming frame 50A and the left and right end faces of the lower back-forming frame 50B spaced apart from each other. Furthermore, the end faces of the upper back-forming frame 50A have narrow, plate-shaped insertion protrusions 53, 53 that project downward, and the end faces of the lower back-seat forming frame 50B have insertion recesses 54, 54 into which the insertion protrusions 53, 53 are inserted. The spaced-apart portions (fitting portions) 55, 55 where the fitting member 51 is fitted are the separated portions (fitting portions) 55, 55. In addition, although not shown in the figure, a narrow locking groove is provided along the entire length of the outer circumference (outer part) of the back-forming frame 50. This locking groove is where the periphery of the back-forming upholstery 52, which will be described later, is locked. In addition, the rear end of the back-forming frame 50 is provided with multiple locking parts (six in this embodiment) for detachably attaching the back-forming frame 50 to the back frame 2A, although these are not shown in the figures. Incidentally, although the insertion projection 53 provided on the upper back-forming frame 50A is shown to be a narrow plate shape in the above description, the shape can be freely selected as long as the insertion projection can be inserted into the insertion recess. Also, although the insertion projection 53 is provided on the upper back-forming frame 50A and the insertion recess 54 is provided on the lower back-forming frame 50B in the above description, this can be reversed, that is, the insertion projection may be provided on the lower back-forming frame 50B and the insertion recess 54 may be provided on the upper back-forming frame 50A.Furthermore, recesses may be provided on both the end faces of the upper back-forming frame 50A and the lower back-forming frame 50B, and a rod-shaped member may be fitted into one of these recesses to form an insertion projection, which can then be inserted into the recess on the other side. In short, it is sufficient that an insertion projection protruding from one end face and an insertion recess receiving the insertion projection are formed on the other end face. Moreover, although the above example shows that the locking groove of the back-forming frame 50 is provided along substantially its entire length, the locking groove does not have to be provided continuously around the perimeter and may be interrupted at various points.

[0023] The fitting member 51 is a member that is fitted into the gap 55 of the back forming frame 50, that is, the gap 55 between the end face of the upper back forming frame 50A and the end face of the lower back forming frame 50B. It is formed by providing inwardly bending clamping arms 51b, 51b at both the left and right ends of the lower surface of a thick plate portion 51a having a predetermined thickness. A locking groove (not shown) is formed on one end to engage with the periphery of the back forming upholstery 52. ​​When the fitting member 51 is fitted into the back forming frame 50, the thick plate portion 51a of the fitting member 51 covers the upper part of the insertion projection 53 of the back forming frame 50, and the clamping arms 51b, 51b of the fitting member 51 clamp the sides and bottom surface of the insertion projection 53. Furthermore, the locking groove of the insertion member 51 is designed to be continuous with the locking groove of the back-formed frame 50 when the insertion member 51 is fitted into the back-formed frame 50.

[0024] The back-forming upholstery 52 is made of an elastic material, that is, a stretchable sheet, and in this embodiment, a mesh material is used. A fastening piece 65 for securing the back-forming upholstery 52 to the back-forming frame 50 is fixed to the periphery of the back-forming upholstery 52. ​​As shown in Figure 3, this fastening piece 65 is made of a narrow strip-shaped plate material and does not encircle the entire periphery of the back-forming upholstery 52, but is divided in several places. Specifically, in this embodiment, it is divided in a total of eight places.

[0025] Next, the procedure for upholstering the chair fabric as described above will be explained with reference to Figure 4. Here, the upholstery will be explained using the seat 1 as an example of the body contact area. Before the upholstery of the seat-forming fabric 22 is attached, the seat-forming frame 20 is not attached to the seat-support shell 1A, as shown in Figure 4(a), and is divided into two parts: the front seat-forming frame 20A and the rear seat-forming frame 20B. First, the insertion projection 23 of the rear seat-forming frame 20B is inserted into the insertion recess 24 of the front seat-forming frame 20A, and the two are joined together. Then, as shown in Figure 4(b), the periphery of the seat-forming fabric 22 is folded back together with the latching piece 35 provided in that area and fitted into the locking groove 26 formed in the seat-forming frame 20, thereby latching the seat-forming fabric 22 to the seat-forming frame 20. Incidentally, in this state, the end face of the front seat-forming frame 20A and the end face of the rear seat-forming frame 20B are in contact and closed to each other, and there are no gaps 25, 25 between them. Therefore, the length of the seat-forming frame 20 in the front-rear direction is shorter compared to the final form shown in Figure 4(d). As a result, the seat-forming upholstery 22 can be attached to the seat-forming frame 20 relatively easily. At this time, the seat-forming upholstery 22 is only subjected to a certain degree of tension on the seat-forming frame 20, and is not fully tensioned. Next, as shown in Figure 4(c), the front seat-forming frame 20A and the rear seat-forming frame 20B are moved away from each other using human hands or a machine, etc., to create gaps 25, 25 between their end faces. Then, the fitting members 21, 21 are fitted into both of these gaps 25, 25, respectively. When the inserting members 21, 21 are fitted, tension is applied to the seat-forming upholstery 22. This tension causes the inserting members 21, 21 to be pressed against both the front seat-forming frame 20A and the rear seat-forming frame 20B, maintaining them between the separated portions 25, 25. At the same time, the seat-forming upholstery 22 maintains tension on the seat-forming frame 20 in the direction of the arrow in Figure 4(d). Finally, the locking portion of the seat-forming frame 20, on which the seat-forming upholstery 22 is stretched, is locked to the hooking portion 13 of the peripheral edge portion 10 of the seat-support shell 1A.

[0026] If it becomes necessary to replace the seat-forming upholstery 22 and remove it from the seat-forming frame 20, simply reverse the above procedure. That is, remove the fitting members 21, 21 that are fitted into the separated portions 25, 25 of the seat-forming frame 20, and bring the front seat-forming frame 20A and the rear seat-forming frame 20B closer together. At this time, the seat-forming upholstery 22 will no longer be under tension on the seat-forming frame 20, so it can be easily removed from the seat-forming frame 20.

[0027] Incidentally, the same procedure as above can be used when attaching the back support fabric 52 to the backrest 2.

[0028] Figure 5 shows another embodiment of the body contact surface forming frame, in this case the seat surface forming frame. Unlike the embodiment shown above, this seat surface forming frame 70 is not constructed by dividing the frame. Specifically, in this example, the rear of the seat surface forming frame 70 is divided approximately in the left-right direction, forming one separated portion 71, and the fitting member 72 is fitted into this one separated portion 71. In this way, it is possible to tension the seat surface forming fabric by a single separated portion without dividing the seat surface forming frame, and in this example, the seat surface forming fabric 73 stretched over the seat surface forming frame 70 will be tensioned in the direction of the arrow in Figure 5(b). Reference numeral 74 in the figure indicates an insertion projection that is inserted into an insertion recess 75 on one end face of the separated portion 71 of the seat surface forming frame 70.

[0029] In the above embodiment, examples were shown in which the body contact surface forming frame had two or one space for the spaced portion, but it is of course possible to provide spaced portions in more locations. Also, in the example where spaced portions are provided in two locations, the spaced portions are positioned opposite each other, but it is not necessary for them to be opposite each other. In short, the spaced portions and insert members provided on the body contact surface forming frame can be provided in any location, any number, and any size, depending on where tension is to be applied to the body contact surface forming fabric and the strength of the tension. In particular, the ability to freely adjust the strength of the tension by changing the inner dimensions of the spaced portions and the dimensions (width, etc.) of the insert members relative to the inner dimensions of the spaced portions is a great advantage of the present invention.

[0030] Furthermore, although the above embodiment shows an example in which the contact surface forming frame can be detachably attached to the support base, it is not necessarily required that the contact surface forming frame be fixed to the support base, and the objectives of the present invention can be achieved even if the contact surface forming frame is fixed to the support base. In other words, while making the contact surface forming frame detachable from the support base is beneficial as it facilitates work not only when assembling the chair but also when replacing the contact surface forming upholstery, tensioning work on the contact surface forming upholstery is still possible even if the contact surface forming frame is fixed to the support base.

[0031] Furthermore, while the insertion protrusions and insertion recesses provided on the contact surface forming frame shown in the above embodiment have the advantage of facilitating the insertion of the fitting member into the separated portion, the objective of the present invention can be achieved even without providing these.

[0032] Furthermore, although a mesh material was shown as an example of the contact surface forming upholstery in the above embodiment, it is not limited to this, and any material that is elastic does not necessarily have to be a mesh material.

[0033] Furthermore, in the above embodiment, an example was shown in which the fastening pieces of the seat-forming upholstery or back-forming upholstery are fitted into locking grooves provided around the seat-forming frame or back-forming frame as a means of fastening the body-contacting surface-forming upholstery to the contact-forming frame, but the means are not limited to this. For example, means such as fastening the periphery of the seat-forming upholstery or back-forming upholstery to the seat-forming frame or back-forming frame with a stapler or the like may be used. In short, as long as the periphery of the body-contacting surface-forming upholstery can be fastened to the contact-forming frame with a certain amount of tension applied, the specific means can be arbitrarily selected. [Explanation of Symbols]

[0034] 1 seat 1A Seat shell (support base) 1B Seat upholstery mechanism 2 Backrest 2A Back frame (support base) 2B Upholstery tensioning mechanism for the backrest 20. Seat surface forming frame (contact surface forming frame) 21 Insertion Member 22 Seat surface forming upholstery (contact surface forming upholstery) 25 Separation part 50 Back side forming frame (contact surface forming frame) 51 Insertion Member 52 Seat surface forming upholstery (contact surface forming upholstery) 55 Separation part

Claims

1. A chair upholstery structure in which a sheet-like upholstery is attached to the parts that come into contact with the body, The chair comprises a support base provided at the point where the body makes contact with the chair, and an upholstery tensioning mechanism attached to the support base, The upholstery tensioning mechanism comprises a contact surface forming frame body formed as an annular frame, with one or more locations of the frame separated to create a gap between one end and the other, an insertion member fitted into the gap of the contact surface forming frame body to expand the contact surface forming frame body, and a body contact surface forming upholstery having elastic force and having its periphery hooked onto the contact surface forming frame body. A chair upholstery tensioning structure characterized in that, after the body contact surface forming upholstery is hung on the contact surface forming frame, the fitting member is fitted into the separated portion of the contact surface forming frame, causing the contact surface forming frame to expand in the tension direction of the body contact surface forming upholstery and apply tension to the upholstery, while the fitting member is pressed by one end and the other end of the separated portion of the contact surface forming frame and maintained in the separated portion.

2. The chair upholstery structure according to claim 1, characterized in that the contact surface forming frame can be detachably attached to the support base by engaging the locking portion or the locking portion provided on the contact surface forming frame with the locking portion or the locking portion provided on the support base.

Images