US2717632A

US2717632A - Folding tablet arm

Info

Publication number: US2717632A
Application number: US313863A
Authority: US
Inventors: Glenn B Morse
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-10-09
Filing date: 1952-10-09
Publication date: 1955-09-13
Anticipated expiration: 1972-09-13

Description

Sept. 13, 1955 G. B. MORSE 2,717,632

FOLDING TABLET ARM Filed Oct. 9, 1952 3 Sheets-Sheet l p 1955 v G. B. MORSE 2,717,632

FOLDING TABLET ARM Filed Oct. 9, 1952 3 Sheets-Sheet 2 /n ven/or p 3, 1955 G. B. MORSE 2,717,632

FOLDING TABLET ARM Filed Oct. 9, 1952 3 Sheets-Sheet 3 ji /3. h?

United States Patent FOLDING TABLET ARM Glenn B. Morse, Grand Rapids, Mich.

Application October 9, 1952, Serial No. 313,863

Claims. (Cl. 155-125) The present invention provides a folding support for a tablet arm mounted on a folding chair. The tablet arm and support may conveniently be mounted on a chair of the type shown and described in the Burnham et al. Patent Number 2,568,269, but is not restricted to use in conjunction with primary chair structures having that particular type of folding action.

A tablet arm of suificient size to be of much use as a writing surface or for supporting books or other items presents a very troublesome problem if an attempt is made to design a folding mechanism for it that is directly tied into the folding movement of the basic chair mechanism so that both fold together. Attempts to produce a mechanism capable of collapsing both the tablet arm and the chair together have either resulted in such awkward folded positions or such expensive mechanism as to make either of these alternatives commercially impractical.

The present invention provides for the folding of a tablet arm support as a substantially separate mechanical system; a part of it, however, being adapted to cooperate with the erected chair structure to establish the erected position of the tablet arm. The tablet arm may be folded without collapsing the chair, if desired.

The folding support for the tablet arm provided by the present invention includes a member hinged on parallel axes respectively to the side of the seat of the chair and to the work-supporting panel. Folding movement of this mechanism involves a rotation of the supporting member about its lower hinge point over into a position substantially parallel to the seat of the chair. This movement carries the tablet arm over into a position superimposed on the seat of the chair.

When it is desired that the tablet arm be maintained in an erected position to provide a working or supporting surface, a coupling member secured to the tablet arm is engaged by a portion of the primary chair structure, preferably a part of a leg member. This engagement performs two functions: (a) the prevention of the rotation of the hinged supporting member, (b) the prevention of the rotation of the working panel about its hinged connection to the supporting member. As long as the coupling member is engaged, the tablet arm is firmly anchored in position. The simplest form of the present invention provides a fixed coupling member requiring that the chair be displaced slightly from fully erected position to disengage the coupling member from the leg. A modified form of the invention, however, provides for a sliding mounting of the coupling member which will permit disengagement from the leg without displacing the primary chair structure from the fully erected position. This latter feature will permit the use of relatively large tablet arms on chairs arranged in closely-packed rows. Under these circumstances, a large tablet arm would usually make it impossible for a person to enter and leave a chair without interfering with his neighbor. Since it is possible to disengage and move the tablet arm to a position where it does not obstruct egress from the chair, the size of the "ice tablet arm may no longer be regarded as limited by the necessity of having room to enter the chair from the front.

The several features of the present invention will be discussed through an analysis of the particular embodiments illustrated in the accompanying drawings. In these drawmgs:

Figure 1 presents a side elevation of an erected folding chair of the type shown in the Burnham et al. application referred to above, and with a tablet arm constructed according to the present invention in the fully erected position.

Figure 2 presents a front elevation of the upper portion of the chair shown in Figure 1.

Figure 3 shows the chair illustrated in Figure l, with the primary chair structure displaced slightly from fully erected position to permit disengagement of the tablet arm supporting mechanism for folding.

Figure 4 shows a view from the front of the upper portion of the chair with the tablet arm and support in an intermediate position.

Figure 5 shows the mechanism illustrated in Figure 4 as it appears when fully collapsed and superimposed upon the seat.

Figure 6 illustrates the folded relationship of the entire chair structure, including the tablet arm.

Figure 7 shows a side elevation of a folding chair mechanism similar to that shown in Figure 1, but provided with a modified form of the coupling member.

Figure 8 shows a perspective view of the coupling member utilized in the Figure 7 mechanism.

Figure 9 shows a view of the chair illustrated in Figure 7 with the chair and tablet arm mechanism in the fully folded position.

Referring to Figures 1 through 6, the primary folding chair mechanism is shown including the front legs 10 and 11, the seat 12, the back panel 13, and rear legs as indicated at 14 in Figure 1. The front and rear legs are pivotally connected to the seat 12 as indicated at 15 and 16, respectively, in Figure 1. The upper end of the rear legs is connected to the associated front leg with a link as indicated at 17 in Figure 3. This link is positioned within the hollow front leg with the chair in the fully erected position, and moves outward through a slot at the rear of the front leg during the folding operation. The details of this mechainsm are shown and described in the Burnham et a1. patent referred to above.

A supporting panel 18 is mounted on a hinge 19 which is also secured to the panel-supporting member 20. This member is mounted on

hinges

21 and 22 secured to the seat 12. Reference to Figure 4 will indicate the folding movement of the tablet arm and the support member.

In order to maintain the panel 18 in the erected position shown in Figures 1 and 2, a coupling member 23 is mounted firmly on the panel 18 and is adapted to engage the upper portion of the front leg 11 of the primary chair structure. The form of the coupling member shown in Figuresl through 6 includes a mounting base 24, a web 25 extending in a plane substantially perpendicular to the panel 18, and a hook portion 26, the hook portion being adapted to firmly grasp the front leg 11.

In. order to fold the tablet arm of the mechanism shown in Figures 1 through 6, it is first necessary to slightly displace the primary chair structure from fully erected position as indicated in Figure 3. This can easily be done by grasping the upper part of the back of the chair with one hand, and with the other hand holding the outer end of the work-supporting panel. An upward movement on both hands will suffice to position the chair as indicated in Figure 3. This slight displacement from fully erected position serves to disengage the hook portion 26 from the front leg, and the supporting member is therefore free to rotate over to a position substantially parallel to the seat 12. Due to the presence of the web 25, it is preferable that the tablet arm 18 be rotated in a clockwise direction (as seen from the front) with respect to the supporing member 20 during the folding movement. This action results in positioning the tablet arm bottom-up on the seat, as shown in Figure 5. With the tablet arm and support folded as shown in Figure 5, the remainder of the chair structure can be moved to the fully folded position shown in Figure 6.

Due to the dimensions of the web 25, the coupling member 23 has a tendency to project considerably beyond the folded chair structure, unless some perhaps undesirable alterations in the proportions of the chair are made. It is possible, for instance, to form the hook member 26 farther upward (as shown in Figure l) with respect to the panel 18. This will result in reducing the amount of projection of the coupling member beyond the chair structure as shown in the view in Figure 6. To do so, however, would mean revising the back panel or the position of the work-supporting panel in a fashion which in particular installations might prove to be undesirable. To avoid this necessity, it is possible to form a coupling member as shown in Figures 7 through 9. In Figure 7, a chair of identical construction as that illustrated in Figure l is shown provided with a similar panel 18 and supporting member 20. The modified coupling member 27 is provided with a base portion 28, a downwardlyextending web 29, and a hook portion 30 attached thereto. The Web 29 of the modified coupling member is formed so as to be substantially parallel to the rear of the seat 12,

and it will be noted in Figure 7 that the position of the web 29 is such that rotation of the supporting member 20 down into folded position brings the web 29 down behind the rear of the seat 12.

In models wherein it is desirable that the occupant of the chair be able to disengage the tablet arm and remove it from a position interfering with his egress from the chair, it is preferable that the base portion 28 of the coupling member be provided with the

elongated slots

31 and 32. These slots are engaged by the heads of the screws 33 and 34, respectively, and the screws are left loose enough to provide a sliding movement of the coupling member to and from a position where the hook portion 30 engages the front leg 11. With this arrangement, a relatively large tablet arm extending substantially across the front of the chair can still be folded if the occupant of the chair will reach around and disengage the coupling member from the front leg. Rotation of the tablet arm to a vertical plane will permit his egress from the chair Without necessitating removing the chair from a row or disturbing his neighbor. The folding movement of the tablet arm and its supporting member (when provided with the modified form of the coupling) can take place while maintaining the tablet arm in a plane roughly parallel to that of the seat. The tablet arm then assumes a position top-up when superimposed upon the seat, and the web and

hook portion

29 and 30 of the coupling will occupy areas having a much reduced tendency to interfere with the stacking characteristics-of the entire folded chair-tablet arm unit. This folded position is shown in Figure 9.

The particular embodiments of the present invention which have been discussed herein, are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appending claims. In these claims,

4 it is my intent to claim the entire invention disclosed herein except as I am limited by the prior art.

I claim:

1. A folding tablet arm for a folding chair, said folding chair having a seat and leg means pivotally connected to said seat, comprising: a panel providing a working surface for an occupant of said chair; a substantially planar panel-supporting member pivotally attached to said panel and to the side of said seat respectively on axis substantially parallel to said side; coupling means slidably mounted on said panel and adapted to move to and from a position engaging said leg means on erection of said folding chair to lock said member and panel against rotation about said axes with respect to said seat.

2. A folding tablet arm for a folding chair, said folding chair having a seat and leg means pivotally connected to said seat, comprising: a panel providing a working surface for an occupant of said chair; a panel-supporting member pivotally attached to said panel and to the side of said seat respectively on axes substantially parallel to said side; coupling means slidably mounted on said panel and adapted to move to and from a position engaging a portion of said chair on erection thereof to lock said member and panel against rotation about said axes with respect to said seat.

3. A folding tablet arm for a folding chair, said folding chair having a seat and leg means pivotally connected to said seat, comprising: a panel providing a working surface for an occupant of said chair; a substantially planar panel-supporting member pivotally attached to said panel and to the side of said seat respectively on axes substantially parallel to said side; coupling means mounted on said panel and adapted to engage said leg means on erection of said folding chair to lock said member and panel against rotation about said axes with respect to said seat.

4. A folding tablet arm for a folding chair, said folding chair having a seat and leg means connected to said seat, comprising: a panel providing a working surface for an occupant of said chair; a panel-supporting member pivotally attached to said panel and to the side of said seat respectively on axes substantially parallel to said side; coupling means mounted on said panel and adapted to engage said leg means on erection of said folding chair to lock said member and panel against rotation about said axes with respect to said seat.

5. A folding tablet arm for a folding chair, said folding chair having a seat and leg means connected to said seat, comprising: a panel providing a working surface for an occupant of said chair; panel-supporting member pivotally attached to said panel and to the side of said seat respectively on axes substantially parallel to said side; coupling means mounted on said panel and adapted to engage a portion of said chair on erection thereof to lock said member and panel against rotation about said axes with respect to said seat.

References Cited in the file of this patent UNITED STATES PATENTS 791,531 Althotf June 6, 1905 1,143,678 Winans June 22, 1915 1,661,937 Fischer et al. Mar. 6, 1928 1,864,750 Moore June 28, 1932 2,048,014 Lochman et al. July 21, 1936 2,452,182 Clawson Oct. 26, 1948