US3640567A

US3640567A - Drop-end seat mechanism

Info

Publication number: US3640567A
Application number: US840981A
Authority: US
Inventors: Robin Howland
Original assignee: PARKER KNOLL Ltd
Current assignee: PARKER KNOLL Ltd
Priority date: 1968-07-11
Filing date: 1969-07-11
Publication date: 1972-02-08
Anticipated expiration: 1989-02-08
Also published as: GB1211807A

Abstract

The invention concerns a drop-end mechanism for chairs and settees, particularly fully upholstered articles. The mechanism comprises an extension member fitted to the frame of the dropend, a stay pivotally connected between the extension member and the frame of the chair and a cam track to guide the end of the extension member as the drop-end is raised and lowered. A particular feature of the invention is that as the drop-end is lowered it moves inwardly relative to the seat to prevent any gap between the seat and drop-end upholstery when in the dropped position. The drop-end is supported from below and, in a preferred arrangement, can be set in an intermediate position.

Description

United States Patent Howland 1 Feb. 8, 1972 [54] DROP-END SEAT MECHANISM 211 Appl. No.: 840,981

3,107,364 10/1963 Simmons ..5/48

FOREIGN PATENTS OR APPLICATIONS 606,014 2/ I926 France ..297/ l 15 819,066 6/1937 France ..5/52

Primary Examiner-Francis K. Zugel Attorney-Fleit, Giffle & Jacobson ABSTRACT The invention concerns a drop-end mechanism for chairs and settees, particularly fully upholstered articles. The mechanism comprises an extension member fitted to the frame of the drop-end, a stay pivotally connected between the extension member and the frame of the chair and a cam track to guide the end of the extension member as the drop-end is raised and lowered. A particular feature of the invention is that as the drop-end is lowered it moves inwardly relative to the seat to prevent any gap between the seat and drop-end upholstery when in the dropped position. The drop-end is supported from below and, in a preferred arrangement, can be set in an intermediate position.

3 Claims, 4 Drawing Figures SHEET 2 OF 2 PAIENTEflrw a 1912 DROP-END SEAT MECHANISM DESCRIPTION This invention relates to a drop-end mechanism for fumiture, particularly fully upholstered furniture.

Many drop-end mechanisms currently available suffer from the disadvantage that, when used on fully upholstered fumiture, a substantial gap is formed, when the end is dropped, between the upholstery of the seat portion and the upholstery of the dropped end portion.

The present invention seeks to avoid this disadvantage.

According to the invention there is provided a drop-end mechanism for furniture comprising an extension member adapted to be secured to the frame of the end to be dropped so as to extend downwardly therefrom, a stay pivotally connected at one end to the extension member ata position intermediate the ends thereof and at the other to a first fixed bracket adapted to be secured to the seat frame forwardly from the lower end of the extension member, a cam track extending forwardly and upwardly from a point adjacent the lower end of the extension member, a second fixed bracket adapted to be securedto the seat frame adjacent the upper end of the cam track, a roller mounted on the lower end of the extension engaging in the track, and a latch adapted to hold the extension in a substantially vertical position with the roller located in the lower end of the track. The latch is releasable to pennit the roller to move upwardly along the track thereby pivoting the extension member into a substantially horizontal position with the inner end engaging upwardly against the second fixed bracket and pivoting the stay member about the first fixed bracket into a substantially vertical position thereby to provide a thrust member adapted to support the dropped end.

With this arrangement, the drop-end pivots about an axis which moves inwardly as the end is lowered into the dropped position. As a result the drop-end is displaced inwardly relatively to the seat thereby filling the gap which would otherwise form in the dropped position between the upholstery of the seat and the upholstery of the drop-end. Not only this, but in the dropped position the dropped end is supported by the stay, which in the dropped position adopts a substantially vertical position and therefore acts as a strut for the dropped end.

While, in the simplest case, the drop-end mechanism of the invention is movable between stable positions, i.e., substantially vertical and substantially horizontal, a preferred arrangement according to the invention permits a stable intermediate position for the drop-end. This stable intermediate position is achieved by suitable shaping of the cam track to provide a midpoint at which the roller engages the upper edge of the track to complete a stable equilibrium in which the extension member lies inclined at an angle to the horizontal.

The invention is illustrated in the accompanying drawings, presented by way of example, in which:

FIG. 1 is an elevation of one end of a drop-end settee incorporating the drop-end mechanism of the invention;

FIG. 2 is a partial end view of the settee;

FIG. 3 corresponds to FIG. 1 with the drop-end in the lowered position; and

FIG. 4 corresponds to FIG. 1 with the drop-end in an intermediate position.

Referring now to the drawings, the settee itself is shown in dotted lines and the drop-end mechanism in full lines for the sake of clarity. The settee is fully upholstered having an upholstered seat 1 and an upholstered end or arm 2. The settee has an interior wooden frame, the various parts of which are only shown insofar as they are necessary for an understanding of this invention. It will be appreciated that the drop-end mechanism is mounted inside the frame so as to be concealed from view.

The drop-end mechanism shown consists of a strong metal extension member 3 firmly secured to a wooden frame member 4 of the arm 2. In the normal upright or vertical position of the arm (FIG. 1) the extension member extends substantially vertically downward into the base of the settee. Pivotally attached to the extension member intermediate its ends by a pivot pin 6 is a stay 5 which, in this first position, extends forwardly and downwardly from the extension member to be rigidly connected at its lower forward end to a rod 7 extending transversely across the settee and pivotally supported at its ends by brackets 8 securely fixed to frame members 9 in the base of the settee.

Extending forwardly and upwardly from adjacent the lower end of the extension'member 3 is a cam track 10 having a specially designed shape, the purpose of which will be described later. In the embodiment shown this cam track is formed by a channel 11 cut in the inside face of a wooden wall panel 12 which forms part of frame at the front of the settee. In an alternative arrangement the cam track can be provided by a suitably shaped metal member secured to the seat frame member. I

Adjacent the upper end of the track 10 is a second fixed bracket 13 securely fixed to a frame member of the seat portion of the settee.

At its lower end the extension member 3 is provided with a roller 14 rotatably mounted on the extension member, the roller engaging in the cam track as shown in FIG. 2. Adjacent the lower end of the extension member is a catch which releasably holds the extension member and the drop-end in the vertical position. This catch comprises an angled bar 15 extending transversely across the settee and pivotally secured at its ends to the frame members 9. Approximately at its midpoint the bar is provided with a foot pedal 16 projecting outwardly from under the end of the settee. A counterbalance weight 15a holds the bar in the locking position shown. Alternatively, the bar may be held in the locking position by a spring. In yet another arrangement the catch may consist of a steel torsion strip fastened at its opposite ends to the frame member 9, the bar being twisted against its inherent resilience out of engagement with the member 3 by application of pressure to the foot pedal 16.

In the position shown in FIG. 1, the arm 2 rests under its own weight on the lower part of the settee frame. Therefore to avoid wear on'the upholstery covering at this point two

metalbearing plates

17,18 are provided, one on the undersurface of the arm and one on the upper surface of the seat portion. These two plates serve a further purpose hereinafter mentioned.

Operation of the mechanismis as follows. As indicated, in the normal upright position of the arm, FIG. 1, the arm rests on the plate 18 supported by the lower frame assembly of the settee. Pivotal movement is presented in one direction by the catch bar 15 engaging against the lower end of theextension member 3, and the opposite direction by the frame member 19.

To lower the arm into the dropped position, FIG. 3, the pedal 16 is depressed to disengage the catch bar 15 from the lower end of the extension member 3. Downward and outward pressure on the arm will now cause the roller 14 to travel upwardly along the cam track 10 so that the extension member 3 pivots in a clockwise direction about the pin 6. Simultaneously, the stay 5 pivots in an counterclockwise direction about the axis of the rod 7. When the roller 14 reaches the upper end of the cam track, the free end of the extension member 3 comes up against the fixed bracket 13 and by this time the stay 5 has reached the substantially vertical position shown in FIG. 3. Indeed, to give special stability in the dropped position the stay may be arranged to move slightly beyond the dead center position. The extension member and am now lie in a substantially horizontal position with the free end of the extension member engaging upwardly against the bracket 13 and supported from below by the stay 15 now acting as a strut or thrust member to carry the weight of the dropped arm.

In this dropped position three points are to be noted. First, the whole arm has been displaced bodily inward relative to its former position. The gap between the upholstery of the seat I and the arm 2 is thus substantially completely eliminated.

Secondly, the arm is firmly supported from below by the stay 5 so/that a substantial weight can be placed on the arm, and thirdly the arm is supported slightly above the lower part of the settee frame and the plate 18 so that fabric-to-fabric contact is eliminated.

To restore the arm to its original position all that is necessary is for the outer end to be raised upwardly and inwardly thereby causing the roller to travel downwardly along the cam track until the lower end of the extension locks into position again behind the catch bar 15.

Referring now to FIG. 4, it is possible, by appropriate shaping of the cam track to arrange for a stable intermediate inclined position for the arm 2. For this purpose, the upper run of the cam track is provided with an intermediate bulged portion 10a. When the roller 14 engages against the bulged portion a stable pattern of forces is set up between the axis of the roller'14, the axis of the rod 7, the axis of the pivot pin 6 and the contact line between

plates

17 and 18 so that the extension member is held at an angle inclined to the horizontal. The essence of this position is that in moving from the vertical position the

plates

17 and 18 slide against each other until the intermediate position is reached. At this position no further movement of the arm ispossible without plate 17 breaking contact with plate 18. This, however, requires a change of thrust which will be against gravity and against the forces which will be placed on the arm in the inclined position when in normal use. The net result is that in this intermediate position a stable equilibrium is set up with the arm held in an inclined position. The precise position at which this equilibrium occurs is determined by the position of the bulge 10a in the cam track 10. To break the equilibrium all that is necessary isfor the arm to be lifted slightly to break the contact between the

plates

17 and 18. The arm can then be pushed inwardly and downwardly into the FIG. 3 position or it can be restored to the original vertical position of FIG. 1.

In order to ensure smooth operation and firm support for the arm, the second extension member and stay will desirably be fitted on the other side of the arm. Slewing of the arm during raising and lowering will be prevented by the rod 7 rigidly connecting the lower ends of the stay members 5 on opposite sides of the arm. In the case of an arm movable only between the two extreme positions, a second cam track on the backwall of the settee is not necessary since no weight is taken by the roller 14 in either of the two extreme positions. However, where an intermediate position is possible a considerable weight is taken by the roller in the intermediate position. It is therefore desirable to provide a second cam track on the backwall of the settee and a roller on the second extension member so that the forces in the inclined position will be evenly distributed.

In addition to the advantages already mentioned, the extreme simplicity of the mechanism will be readily appreciated. It will be noted too that by suitably counterbalancing the lower end of the extension member the drop-end can be raised and lowered with a minimum of effort.

While the invention has been particularly described with reference to a settee, it will be appreciated that the mechanism of the invention can be used with any form of seat where a drop-end function may be desired, e.g., the arm of an armchair. Alternatively the mechanism can be used on the back of a chair or settee where a reclining or dropped position is desired. Accordingly the phase drop-end" where used in this specification and claims is intended to embrace both drop arms and reclining backs of chairs and settees and not just drop arms.

I claim:

1. In an article of furniture having a drop-end, a dropend mechanism comprising an extension member rigid with said drop-end and extending downwardly from said drop-end, a roller mounted on the lower end of said extension member, a first bracket secured at a fixed location within said article of furniture at a point spaced forwardly from the lower end of said extension member when said drop-end is in an upright position, a stay pivotally connected at one end to said extension member intermediate the ends thereof and at the other end to said first bracket, a second bracket secured at a fixed position located forwardly and upwardly from said first bracket, a cam track extending from a rearward point adjacent the end of said extension member when said drop-end is in an upright position, said cam track upwardly and forwardly extending to a point adjacent the second bracket, a latch adapted to hold said extension member in a substantially vertical position with the roller located in the lower end of said track, and means for releasing said latch to permit the roller to move upwardly along said track thereby pivoting the extension member into a substantially horizontal position with the inner end engaging upwardly against said second fixed bracket and pivoting the stay member in a forward direction about said first bracket into a substantially vertical position, thereby to provide a thrust member to support the drop-end which has moved bodily forwardly in the dropped position, so that said drop-end is positioned against said article in both the upright and the dropped position.

2. A drop-end mechanism according to claim 1, wherein the cam track is shaped to provide a midpoint at which the roller engages the upper edge of the track to hold the drop-end in an inclined position intermediate the vertical and dropped positions.

3. A drop-end mechanism according to claim 1 wherein the article of furniture is upholstered and is selected from dropend armchairs, drop-end settees, reclining back chairs, and reclining back seats, such furniture having an inner frame supporting said upholstery, and further wherein the cam track is located in such a way so that no substantial gap between the upholstery of the seat portion and the upholstery of the drop end is created when said dropend is lowered.

Claims

1. In an article of furniture having a drop-end, a drop-end mechanism comprising an extension member rigid with said drop-end and extending downwardly from said drop-end, a roller mounted on the lower end of said extension member, a first bracket secured at a fixed location within said article of furniture at a point spaced forwardly from the lower end of said extension member when said drop-end is in an upright position, a stay pivotally connected at one end to said extension member intermediate the ends thereof and at the other end to said first bracket, a second bracket secured at a fixed position located forwardly and upwardly from said first bracket, a cam track extending from a rearward point adjacent the end of said extension member when said drop-end is in an upright position, said cam track upwardly and forwardly extending to a point adjacent the second bracket, a latch adapted to hold said extension member in a substantially vertical position with the roller located in the lower end of said track, and means for releasing said latch to permit the roller to move upwardly along said track thereby pivoting the extension member into a substantially horizontal position with the inner end engaging upwardly against said second fixed bracket and pivoting the stay member in a forward direction about said first bracket into a substantially vertical position, thereby to provide a thrust member to support the drop-end which has moved bodily forwardly in the dropped position, so that said drop-end is positioned against said article in both the upright and the dropped position.

3. A drop-end mechanism according to claim 1 wherein the article of furniture is upholstered and is selected from drop-end armchairs, drop-end settees, reclining back chairs, and reclining back seats, such furniture having an inner frame supporting said upholstery, and further wherein the cam track is located in such a way so that no substantial gap between the upholstery of the seat portion and the upholstery of the drop-end is created when said drop-end is lowered.