Ladder chair

Abstract

A chair ladder in which the back of the chair is formed with a pair of spaced rods on either side of the chair seat with the rods pivotally interengaged with one another by a series of spaced, flat, rung-forming members which permit the back of the chair to function as a parallelogram and pivot to and from an upright, back position and an inclined parallelogram position in which the rungs extend between the rear and forward rods forming the rear legs.

Description

RELATED CASES

[0001] Applicant claims the benefit of Israeli Application No. 144478, filed Jul. 22, 2001, for an invention entitled LADDER CHAIR.

SUBJECT MATTER OF INVENTION

[0002] The present invention relates to a chair that may be converted to and from a ladder.

[0003] 1. Background of Invention

[0004] Heretofore, chairs have been frequently used to stand on as substitute ladders. The use of chairs for such purposes, however, is quite limited since chairs usually have a seat that is no more than seventeen inches high and is not provided with features which provide safety to the person standing on them. Chairs are not ordinarily designed to climb on with rungs that make using the unit as a chair comfortable. Designs that are used for converting chairs to ladders are complicated and expensive to make, not comfortable to use, and not secure enough for safety when used. Additionally, these chairs that are convertible to ladders do not ultimately provide a sufficient height to permit many common uses.

[0005] 2. Subject Matter of Invention

[0006] It is an object of the present invention to provide a chair ladder combination which is inexpensive to make, comfortable to use as a chair, and safe to use as a ladder for climbing to heights substantially higher than the normal height of the chair seat. It is a further object of the present invention to provide a chair ladder combination which is comfortable to use as a chair without the need of specifically modifying the shape of the chair for sitting purposes.

[0007] In the present invention, there is provided a chair in which the back legs of the chair and the back of the chair form the ladder of the chair ladder combination. The back legs of the chair are connected to the seat with a special pivot that permits angular movement of the back legs relative to the seat of the chair. The front legs are rigidly secured to the front of the seat in a conventional fashion. Alternately, the front legs may fold to and from a locked position normal to the seat using conventional mechanisms. In converting the unit to use as a ladder, the seat, which connects to the back legs, is oriented in a conventional horizontal chair position. After the back legs are pivoted to a ladder position, rungs which may be conventionally round or flat as illustrated and which are connected to the legs, are pivoted from a vertical to a horizontal position to become rungs of the ladder. The back legs forming the seat can extend to or above the seat position depending upon the particular embodiment of the chair desired. If the chair is designed with a back, the ladder can extend a normal chair having a seat of seventeen inches to a ladder having a height of forty-seven inches or more. Chair ladder combinations and such may be used as kitchen chairs and thus converted into a ladder extending substantially higher than the seat level of the kitchen chair.

[0008] The ladder rungs may be pivoted to the back legs and are designed to be wider than ordinary rungs so the ladder is more comfortable and safe. The rungs may be pivotally fixed to the legs permanently.

[0009] In the present invention, the back of the chair may be pivoted with the rungs rotating about the legs or back of the chair to a horizontal position from a vertical position when the back of the chair is upright. A feature of the present invention provides a hinge on the back legs which includes a locking device which is open to permit angular movement of the back legs to tilt forward, letting the chair device reform from an upright chair to a ladder, and, then when desired, to close it back to its original chair position in a manner in which it is locked into a chair position.

[0010] A principal feature of the present invention is to provide rungs for the ladder on the back of the chair and not from its side with the rungs also forming the chair back. Another feature of the present invention is to provide a chair/ladder combination in which the back of the chair pivots from a back position to a ladder position.

DRAWINGS

[0011] The foregoing objects and advantages of the present invention may be more clearly understood in connection with the accompanying figures which are intended to describe a preferred embodiment of the invention and are intended not to limit the scope of the invention.

[0012] In the drawings:

[0013] FIG. 1 is a side view of the chair ladder combination in a closed position;

[0014] FIG. 2 is a side view of the chair ladder combination in an open position;

[0015] FIG. 3 is a front view of the chair ladder as shown in FIG. 1;

[0016] FIG. 4 is a top view of the chair ladder as shown in FIG. 1;

[0017] FIG. 5 is a detail of the rear legs illustrating a pivotal mechanism;

[0018] FIG. 6 is an isometric view of the chair ladder of the present invention; and

[0019] FIG. 7 is a cross sectional detail of the push button mechanism at one side of the seat.

DETAILED DESCRIPTION OF THE DRAWINGS

[0020] The present invention may be made of a wide range of materials suitable for manufacturing chairs and ladders including, for example, wood steel or suitable plastic. In the present invention, FIG. 1 illustrates the chair ladder from the side. In this arrangement, a conventional seat 1 which may have a standard, rectangular, planar view as illustrated in FIG. 4 is formed with a pair of front legs 6 conventionally connected to the front corners of the seat 1. Rear or back legs are formed from two parts or components. These include a forward part in the form of a pair of elongated rod 4 on either side of the seat as illustrated in FIG. 3 and a pair of rear rods 5 extending parallel to the front rods 4 and co-extensive for at least part of its length. The pair of forward rods 4 may extend upwardly beyond the rear rods 5. The rear rods 5 may be slightly elevated from the floor to enable the device to be open from a chair position to a ladder position. The difference in height is illustrated in FIG. 1. The back legs formed with the rods 4 and 5 is illustrated in FIG. 1 in a closed or chair position. As illustrated in FIG. 1, a pivot 2 on rods 5 permits rotation of the rear legs to and from pre-determined angles illustrated in FIGS. 2 and 6, from the vertical orientation shown in FIG. 1. Forward rods 4 are connected to the rear rods 5 by a series of rungs 3 with the rungs 3 having flat, rectangular, platform shapes as best illustrated in FIG. 6. The rungs 3 are pivoted at their forward corners to the rods 4 in spaced relation to one another and at their rear corners to rods 5 also at their corners. The rungs 3 are preferably uniformly spaced apart to permit the rods 4 and 5 to move to and from the positions shown in FIGS. 1 and 2 with the rungs forming parallel platforms when the rear legs take the form of FIG. 2. As illustrated, several of the rungs 3 may extend above the seat 3 and in this position form a portion of the back as illustrated in FIG. 3 when the rear legs are in their chair position as illustrated in FIG. 1.

[0021] FIG. 2 illustrates the chair ladder in its open position. Because the rods 4 and 5, together with the rungs 3 form a parallelogram, the unit takes on an inclined orientation to form an inclined ladder. Rungs 3 rotate in FIG. 2 from the vertical orientation as shown in FIG. 1 and thus function as ordinary flat rungs of a ladder.

[0022] As illustrated in FIG. 1 and by the dotted lines in FIG. 2, the rods 4 may extend higher than rods 5 and may be joined together with a cross bar to provide a hand grip at the upper most part of the ladder for a person to grasp when climbing the ladder. Pivot 2 is designed to permit movement only to the pre-designed angle shown in FIG. 6. Pivots 7 interengage the rungs 3 and the rods 5 at the front of the rungs 3, as well as interengage the rungs 3 and rods 4 at the rear of the rungs.

[0023] There is provided an optional feature in the form of a link 21 shown in FIG. 1 with one end of the link 21 pivotally secured to the rods 4 and the other ends of the link 21 slideably engaged in a tracks 31 which is located on either side of the seat 3. The unit as illustrated when used as a ladder, is particularly designed for household uses.

[0024] In FIG. 3, there is shown in some detail the arrangement in which the rungs 3 function as part of the back of the chair. The forward rods 4 are connected to the rungs and the rear rods 5 to permit the rungs to pivot to the horizontal ladder position from the vertical position illustrated in FIG. 3.

[0025] In FIG. 4, the top view shows the relation of the forward rods 4 and rear rods 5. In this arrangement, the forward rods 4 may be smaller in cross-sectional view than the rear rods 5 and may be formed of material different from the rear rods 5. Thus rods 5 may be made of wood while rods 4 are made of steel.

[0026] In FIG. 5, there is an enlarged view of the pivot 2 shown in FIG. 1. In this arrangement, pivot 8 is wider than the width of rear rods 5. This permits an arrangement which is somewhat stronger than would be the case if it were not. In this arrangement, a triangular opening or hole 9 in the pivot 8 permit outwardly extending flanges 10 which are integrally formed with a seat 1 limited movement between the upper and lower edges of the hole 9. This allows seat 1 and rear legs to pivot relative to one another over a limited arc. As illustrated in FIG. 7, seat 1 has a hole 18 in one side. An inner push bottom 15 is positioned in the hole 18 with one end spring loaded against spring 14, also positioned in hole 18, at the inner end thereof. The other end of the button 15 extends into a coaxial hole in leg 5 and fixes the leg 5 relative to the seat as long as the button 15 spans these holes. A second bottun 16, coaxial with button 15 is slideably engaged in the coaxial hole in leg 5 and maybe selectively pushed to disengage button 15 from spanning these holes to a position entirely within the hole 18 in the seat, thus permitting relative movement of the seat 1 and leg 5. Thus, in the chair position, the push button 15 engages the hole 18 in the side of the seat preventing the back legs from moving.

[0027] FIG. 6 illustrates, as noted above, the chair ladder in a ladder position.

Claims

1. A chair-ladder convertible between a chair position and a ladder position;

comprising a seat and a back pivotally interengaged with the rear edge of said seat, said back having a pair of spaced rear legs, means pivotally engaging the legs to the rear of the seat, a plurality of rungs, pivotally engaging and extending between the legs and means for positioning the chair-ladder in a selected chair or ladder position.

2. A chair-ladder as set forth in claim 1 wherein said rear legs are each formed of a pair of spaced parallel rods with the rungs positioned between the legs and having on each side of the rungs a pair spaced connections pivotally interengaging each of the rungs at their ends at spaced positions to each rod.

3. A chair ladder as set forth in claim 2 wherein each rung is formed of a flat elongated member.

4. A chair ladder as set forth in claim 2 having means for locking the back selectively in a ladder position or a chair position.

5. A chair ladder as set forth in claim 4 wherein said ladder has rungs that extend above the chair seat when the back is in a ladder position.

6. A chair ladder as set forth in claim 5 including means for limiting the relative movement of said seat and back.

7. A chair-ladder having a seat for supporting a sitting individual and a back connected to the seat with rear legs defining the rails of a ladder and with a plurality of rungs extending between the legs to function as ladder rungs and the back support of the seat.