US3446532A - Chair - Google Patents

Description

May 27, 1969 v H. w. CRAMER CHAIR Filed March 13. 1967 INVENTOR Harold W. Creme/ ATTORN s.

United States Patent US. Cl. 297-312 7 Claims ABSTRACT OF THE DISCLOSURE A chair seat for olfice chairs which are adjustable in height, the seat having a rear portion and a front portion, the two portions being hingedly interconnected to permit swinging of the front portion from an initial position where the front portion and rear portion are in a common, substantially horizontal plane to a second position where the front portion extends angularly downwardly from the rear portion; there being means for adjusting the extent of swinging movement of the front portion into its downwardly extending position, such adjusting means taking several forms, such as a slide block having an operating member to secure the same in a selected position; a turnbuckle interconnecting the front portion of the chair seat with the standard of the chair; a linkage of fixed length to swing the front portion downwardly when the rear portion is tilted rearwardly; and adjusting means in the form of a screw interconnecting the front portion and the rear portion.

This invention relates to chair seats for oflice chairs, which oflice chairs are normally adjustable in height so that the user thereof can be positioned in the most comfortable position relative to the work surface. In many instances, the work surface is of unusual height, thereby necessitating elevation of the chair seat to a point where a person of shorter stature cannot comfortably place his feet on the floor. In attempting to meet this problem some chairs have been provided with rungs adjacent the base thereof or other equivalent structure upon which the user of the chair, when it is elevated to an extraordinary height, may rest his feet.

However, such a solution 'has not been universally satisfactory and it is, therefore, the primary object of this invention to provide, in an office chair or the like, a chair seat having a rear portion and a front portion, the front portion being swingable relative to the rear portion so that, when the chair seat is necessarily elevated to a height where the user thereof cannot comfortably place his feet on the floor, the said front portion may be swung angularly downwardly with respect to the rear portion. Hinge means interconnect said portions to allow said front portion to swing downwardly from the substantially horizontal plane in which it is initially positioned, thus permitting the user of the chair to rest his feet on the floor in a comfortable manner, the downward inclination of the front portion of the chair relieving pressure on the underside of the legs of the user thereof as would be exerted if the entire chair seat were maintained in a horizontal plane when the chair was elevated to an unusually high position.

' It is a further important object of this invention to provide means for adjusting the extent of downward swinging movement of the front portion of the chair seat to the end that the user thereof may particularly adjust the angle of inclination of said front portion to this personal comfort.

Yet another object of this invention is to provide various adjusting means as will hereinafter be described, certain of said means being adapted for use in connection with a chair seat wherein the rear portion of the seat remains in a substantially horizontal plane, other of said adice justing means being adapted for use with a chair wherein the rear portion of the seat is tiltable rearwardly.

Other objects include details of construction which will become apparent from the following specification and ac companying drawing, wherein:

FIGURE 1 is a side elevational view of an entire chair showing the chair seat with one form of adjusting means;

FIG. 2 is a fragmentary, sectional view showing in greater detail the adjusting means of the chair seat as illustrated in FIG. 1;

FIG. 3 is a fragmentary, top plan view thereof;

FIG. 4 is an enlarged, fragmentary bottom plan view thereof;

FIG. 5 is a fragmentary, side elevational view showing another form of adjusting means;

FIG. 6 is a fragmentary, side elevational view showing a form of adjusting means wherein the rear portion of the chair seat is tiltable; and

FIG. 7 is an enlarged, fragmentary view showing yet another form of adjusting means.

The typical oflice'chair 10 includes a base 12 made up of a plurality of legs, rollers normally being provided at the lowermost end of said legs to facilitate movement of the chair; a standard 14 carried by said base 12; a spider 16 carried at the upper end of said standard; a chair seat 18 supported by said standard; and a back 20 for the chair 10. It will be appreciated that standard 14 is normally carried by base 12 in such a manner that the overall height of the chair may be adjusted to accommodate comfortably a user thereof.

When the height of the chair 10 is adjusted to a point where the user can comfortably work on a given surface, said surface is many times of such height that the user of the chair 10 cannot comfortably place his feet upon the floor which supports chair 10. If an attempt is made by the user to place his feet upon the floor, the conventional chair seat, which remains in a horizontal plane, will exert an undesirable upward pressure on the thighs of a person sitting in the chair, resulting in substantial discomfort and adverse working conditions.

In the present invention, a chair seat 18 is provided, which seat has a rear portion 22 and a front portion 24, the front portion being swingable relative to the rear portion whereby said front portion may be inclined angularly downwardly with respect to the rear portion to thereby lessen the upward pressure on the legs of a user of such chair 10 and permit a more comfortable working posture.

While portions 22 and 24 are of the same width, rear portion 22 is of greater depth and, therefore, comprises the major area of the chair seat 18, front portion 24 comprising a minor area thereof in the nature of one-third of the total area of the overall surface of chair seat 18. The spider 16 is connected only to rear portion 22, fixedly supporting the same but permitting controlled swinging movement of the front portion 24 in a downward direction as will be hereinafter described.

In the preferred embodiment of the invention illustrated in FIGS. 1-4, the front portion 24 is articulated, consisting of at least a pair of hingedly interconnected sections 26, one of said sections being connected to the' rear portion 22 as by a hinge 28 whereby the front portion may be swung downwardly to the position shown i FIG. 2 of the drawing for instance.

To permit such swinging movement of the front portion 24, a plate 30 is disposed in overlying relationship to the articulated sections'26, one end 32 of the plate being connected to the outermost of sections 26, the inner end 34 of plate 30 being movably connected to a block 36, which block 36 is disposed within a recess 38 provided in the upper surface of rear portion 22 of seat 18.

An operating member 40 is carried by block 36 and extends downwardly therefrom through a slot 42 provided in rear portion 22, slot 42 being in communication with recess 38. Operating member 40 is in the nature of a threaded stud having an operating handle 44 at the free end thereof, said free end and, therefore, operating handle 44, normally being disposed beneath the chair seat 18 as clearly shown in FIGS. 1 and 2 of the drawing. When operating handle 44 is rotated in one direction it causes an annular ring 46 to be brought into engagement with the lower face of a strip 48 secured to the bottom of rear portion 22, thereby locking the block 36 in a desired position against movement.

When it is desired to swing front portion 24, operating handle 44 is rotated in the opposite direction, thereby releasingring 46 and permitting movement of block 36 within recess 38. The user can then press downwardly on plate 30 causing the front portion 24 to swing downwardly with respect to rear portion 22, which rear portion maintains its substantially horizontal position. When the desired position of adjustment of front portion 24 is reached, operating handle 44 can then be rotated to again lock ring 46 and therefore block 36 against movement, thereby securing the front portion in a selected position with respect to rear portion 22. It will be noted that a portion of the hinge 28 embraces slot 42 whereby to define an edge 50 which serves as a stop for the threaded stern of operating member 40, thus limiting the possible extent of downward swinging movement of front portion 24.

It is contemplated that the chair seat 18 will support a cushion 52 substantially conventional in construction, and that cushion 52 will be provided with a cover 54, which cover 54 will, in turn, be provided with gussets such as 56 therein to thereby permit cushion 52 and cover 54 to accommodate themselves to the configuration of the overall chair seat when front portion 24 is swung to its downwardly inclined position with respect to rear portion 22. A similar cushion and cover assembly is contemplated for the remaining forms of the invention hereinafter de scribed, it only being important that the cushion be of a material, such as sponge rubber or the like, and the cover be provided with gussets so that the cover and the cushion may cooperate in accommodating themselves to the upper surface of the chair seat 18 as the same is varied through the swinging of front portion 24.

In the form of the invention illustrated in FIG. 5, the front portion 24 takes the form of a single length of material, said length of material being connected with the rear portion 22 of the seat 18 by a hinge 58, whereby said front portion 24 may be swung relative to said rear portion 22. The structure shown in FIG. of the drawing includes a turnbuckle 60 which has one end thereof connected to front portion 24 as by a bracket 62, the other end of the turnbuckle 60 being connected with the spider 16 as by a clamp 64 whereby, upon actuation of an operation knob 66, the overall length of turnbuckle 60 can be decreased, thereby causing front portion 24 to swing from its initial position wherein it and rear portion 22 are in a common, substantially horizontal plane to a position wherein said front portion 24 is disposed in a position extending angularly downwardly with respect to said rear portion 22. Here again, a cushion and cover will be provided for the chair seat 18 which will be of such a construction to accommodate themselves to the portions 22 and 24 of the seat when it is in the position shown in FIG. 5 of the drawing. As can be appreciated, the user of the chair may, by convenient actuation of operating knob 66, create the desired extent of angular inclination of front portion 24.

The form of the' invention illustrated in FIG. 6 is particularly designed for chairs wherein the seat 18 is tiltable rearwardly about a horizontal axis such as 68, spider 16 being interconnected with standard 14 in such a manner as to permit rearward tilting of the chair seat 18 and, most particularly, rear portion 22 thereof.

Front portion 24 is secured to rear portion 22 as by a hinge 70. A linkage 72 of fixed length interconnects front portion 24 with the standard 14, said linkage being connected to front portion 24 as by a bracket 74, and to standard 14 as by a clamp 76, whereby, when rear portion 22 is tilted rearwardly about axis 68, the front portion 24 will, as a result of being held against tilting movement by linkage 72, assume a position extending angularly downwardly from said rear portion 22. The extent of downward inclination of front portion 24 can be predetermined by the length of linkage 72, said length remaining fixed during the tilting of rear portion 22.

In the embodiment of the invention illustrated in FIG. 7, front portion 24 is connected to rear portion 22 by a hinge 78, said portions being additionally adjustably interconnected by a screw 80, screw having one end coupled to the front portion 24 as by a U-shaped bracket 82 which receives the free end of screw 80, there being a bracket 84 rigidly secured to the underside of rear portion 22 and carrying a bearing 86 to rotatably support the screw 80 intermediate the ends of the latter. An operating knob 88 is provided at the other end of screw 80, which knob is positioned to be conveniently operated by the user of the chair. Upon rotation of screw 80 in one direction, the front portion 24 is caused to swing downwardly about hinge 78 so that said front portion 24 is inclined angularly downwardly with respect to rear portion 22. Upon rotation of the screw 80 in the opposite direction, said front portion 24 can be repositioned in the same, substantially horizontal plane in which rear portion 22 remains. As is apparent from FIG. 7, the downward swinging movement of front portion 24 is limited in that the rear edge 90 thereof will, after a predetermined angularity has been achieved, be brought into abutting engagement with the front edge 92 of rear portion 22, the meeting of said edges serving to stop or limit the relative downward inclination of front portion 24 with respect to rear portion 22. The same is true with the structure shown in FIG. 5 of the drawing.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In combination with a chair having a base, a standard carried by said base and a back, a chair seat supported by said standard and having a rear portion and a front portion, said front portion being swingable relative to said rear portion; hinge means interconnecting said front portion and said rear portion, said portions initially lying in a common, substantially horizontal plane, said front portion being swingable into a plane extending angularly downwardly from said horizontal plane; and means for adjusting the extent of swinging movement of said front portion relative to said rear portion, said front portion being articulated and consisting of at least a pair of hingedly interconnected sections, there being a plate overlying said sections, one end of said plate being connected to the outermost of said sections, the other end of said plate being movably connected with said rear portion of the chair seat.

2. The invention as set forth in claim 1, said adjusting means being in the form of an operating member coupled to said inner end of the plate and movable therewith, said member being releasable to permit shifting of said front portion and lockable to secure said front portion in a selected position with respect to said rear portion.

3. The invention as set forth in claim 2, there being a block secured to said other end of the plate, the rear portion of said seat having a recess formed therein, said block being movably disposed within said recess, said operating member being carried by said block and depending therefrom, said rear portion having a slot formed therein for receiving said operating member.

4. In combination with a chair having a base, a standard carried by the base and a back, a chair seat supported by said standard, said seat having a front portion and a rear portion, each of said portions having an upper surface and a lower surface; hinge means joining the adjacent lower surfaces of said portions whereby said portions may be shifted from an initial position in a common, substantially horizontal plane to a position with said front portion being angularly disposed with respect to said rear portion and with said upper surfaces of said portions being spaced apart above said hinge means; and means for limiting the extent of shifting movement of said front portion.

5. The invent-ion as set forth in claim 4, said limiting means including a plate overlying the upper surfaces of said portions, said plate being connected to each of said portions in such a manner as to permit limited relative shifting movement thereof.

6. The invention as set forth in claim 5, said plate being disposed in opposed relation to said hinge means.

7. The invention as set forth in claim 6, said front portion consisting of at least a pair of hingedly interconnected sections.

References Cited UNITED STATES PATENTS Peck et al 297201 May 297433 Meighan 297201 Milner 297284 Thurn 297312 Bank et al. 29789 Borenstein 297313 Johnston 297433 Schneider 297312 Anderson 297284 U.S. Cl. X.R.

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