Assembly for Holding and Tensioning a Webbing

This invention relates to an assembly for holding and tensioning a webbing, and has particular application to the furniture field to hold and tension webbing that is stressed by a person seated on the webbing.

Holding and tensioning devices are known, one of which is disclosed in Olsen U.S. Pat. No. 2,006,277 which issued June 25, 1935. The Olsen patent utilizes a bar which is secured to the edge of a webbing, and which is pulled beyond a socket so that it may be slipped into the socket to be held in place, holding and tensioning the webbing. One problem with this assembly is that the webbing must be stretched beyond its ultimate stretch in the completed article of furniture in order to position the bar within the holding socket.

The present invention overcomes this difficulty by utilizing male and female fastening members, in which the male member is levered into engagement with the female member without the need for stretching the webbing in excess of its final stretch in the completed article of furniture and without requiring the male member to be manipulated around (over and under) a socket as in the Olsen patent.

The following detailed description describes a representative and presently preferred embodiment of the invention.

FIGS. 1 and 2 are perspective views showing the seat portion of a chair embodying the present invention.

FIG. 3 is a perspective view of the male and female members constituting parts of the present invention, prior to being assembled together.

FIGS. 4 to 7A are views, some in section, showing the interengagement of the male and female members of FIG. 3 in holding and tensioning a webbing.

Referring to FIGS. 1 and 2, a tubular framework 10 is shown for a chair, in which rectangular portions 10a, 10b, 10c, and 10d define the framework of the chair seat, while frame portions 10e, 10f, 10g and 10h define the legs of the chair. A webbing 12 defines the seat of the chair, and includes opposed edge portions 12a and 12b which carry thereon male members 14 which are adapted to be engaged with female members 16 that are fastened to opposing seat frame pieces 10b and 10d. The male members 14 along one edge of the webbing 12 are engaged with the associated female members 16 on one seat frame portion, and the webbing 12 is then stretched and the opposed male members 14 are engaged with the associated female members 16, as will be described in more detail below, to form the completed seat assembly shown in FIG. 2.

FIG. 3 shows the details of the male and female members. Specifically, the female member 16 is formed with opposed side walls 16a and 16b, a first abutment surface 16c and a second abutment surface 16d, with these latter abutment surfaces perpendicular to each other and to the side walls 16a and 16b. The male member 14 is formed with opposed side walls 14a and 14b, a first abutment surface 14c, and a second abutment surface 14d, with these latter abutment surfaces perpendicular to each other and to the side walls 14a and 14b.

The female member 16 is advantageously attached to the frame member 10d by being spot welded thereto along curved surfaces 16e and 16f which engage the tubular frame section 10d. As thus held in position, it will be noted that the abutment surface 16c is spaced from and faces the frame portion 10d so as to leave a gap 18 therebetween.

The male member 14 is secured to the edge portion of the webbing 12, typically by being screw-fastened thereto through use of a screw 20 (FIGS. 5 to 7) that passes through a hole 22 in male member 14 and is threaded into a bar 24 that is secured inside a flap along the edge of the webbing 12. The webbing is thus attached to webbing attachment surface 14d' which is opposed to and forms an acute angle with abutment surface 14d (FIG. 3). As is evident from FIG. 3, the webbing attachment surface 14d' and the abutment surface 14d together constitute surfaces of a wedge-shaped portion of the male member 14.

When the male member 14 engages the female member 16, the respective abutment surfaces 14c and 16c engage each other, as do the respective abutment surfaces 14d and 16d. In assembled condition, the opposed walls 14a and 14b of the male member are positioned between the opposed walls 16a and 16b of the female member. It should be noted that the male member 14 includes a first step portion 14e (FIG. 3) that includes a surface (14c) that faces away from the frame portion 10d and constitutes the first abutment surface of that male member. This first step portion is positioned within the gap 18 noted above, i.e., the gap between the frame 10d and the abutment surface 16c of the female member 16. The second abutment surface (16d) of the female member, starting at its first abutment surface 16c, extends away from the frame portion 10d. The second abutment surface (14d) of the male member 14 which engages the second abutment surface 16d of the female member is defined by one of the surfaces of a second step portion 14f of the male member.

FIGS. 4 to 7 show how the male member is levered into engagement with the female member (assuming that the male and female members along the opposite edge of the webbing are already interengaged). The step portion 14e of the male member is positioned within the gap 18 (FIG. 5). Next, a lever 26, such as a screwdriver, is positioned with its tip portion bearing against a surface of the hole 22 in the male member 14. The lever bears against an edge of a cut-away portion 16g of the female member which registers with the hole 22 in the male member (FIG. 6). With the leverage thus applied, and the lever moved as shown by arrow 28 in FIG. 6, the webbing 12 is tensioned and the male member 14 is snapped into engagement with the female member 16 (FIG. 7). FIG. 7a is a sectional view, similar to that of FIG. 7, but not taken through the screw 20, showing the interengagement of the abutment surfaces 14c, 16c and 14d and 16d of the male and female members. A person sitting in the chair formed from the framework of FIGS. 1 and 2 will apply a seating stress against the webbing as shown by arrow 30 in FIG. 7. That stress tends to cause continued engagement of the male and female members 14 and 16. It will be noted from FIG. 7 that the tension in the webbing 12 acts at an angle to the plane of the abutment surfaces 14d and 16d, thus creating a moment that urges the abutment surfaces together.

It will be noted from FIGS. 4 to 7a that the webbing 12 does not have to be excessively stretched in order to cause engagement of the male member 14 with the female member 16. There is no moving of the male member over and around and then under a socket portion of the female member, as is necessary in the Olsen patent, cited above.

The invention thus provides a simple yet highly effective assembly for holding and tensioning a webbing. Any suitable number of male and female members may be included, spaced along opposed edges of a webbing, to hold and tension that webbing within a framework. As noted above, the male and female members along one of two opposed webbing edges are interengaged, and then the male members along the opposite webbing edge are levered into engagement with the associated female members. Disengagement of the male and female members is achieved by prying with the edge of a screwdriver or similar instrument at the location 32 shown in FIG. 7, i.e., pushing upwardly against the female member 16 and downwardly against the male member 14 to cause disengagement of the abutting surfaces 14c, 16c and 14d, 16d.

It will be appreciated that the presently preferred embodiment of the invention is subject to modification. Accordingly, the invention should be taken to be defined by the following claims.