(No Model.) I I 2 Sheets-Sheet 1. W. I. BUNKER. PLATFORM ROCKING CHAIR.
No. 569,447. Patented Oct. 13, 1896.
$%WIIUIINIIMW v 2 Sheets-Sheet 2.
(-No Model.)
W. LBUNKER. PLATFORM ROUKING GHAIR.
Patented 001:. 13,1896.
WWII-- THE Noam; vcrzas c0, rnomuwu, WASHRIGT UNITED STATES PATENT OFFICE.
IVILLIAM I. BUNKER, OF LA GRANGE, ILLINOIS.
PLATFORM ROCKING-CHAIR.
SPECIFICATION forming part of Letters Patent No. 569,447, dated October 13, 1896.
Application filed December 12, 1893- Serial No. 493,482. (No model.)
To (LIZ zvhont it nuty (Bo/warm:
Be it known that 1, WILLIAM I. BUNKER, a citizen of the United States, residing at La Grange, Illinois, have invented certain new and useful Improvements in Platform Rocking-Chairs, of which the following is a specification.
My invention, while it has relation to platform rocking-chairs, has more specifically to do with the means by which the rocking is effected; and the invention consists, in general terms, in the construction and arrangement of parts as hereinafter described and claimed.
In the drawings, Figure 1 is a side elevation of a platform rocking-chair containing my improvements; Fig. 2, a plan view of a section taken inline 2 of Fig. 1; Fig. 3, a front elevation of arocking-chair containing my invention; Fig. 4, a side elevation of a modification, and Fig. 5 a side elevation of still another modification.
In making myimproved platform rockingchair I preferably make the base A of the chair of one piece of wood, as shown in Fig. l of the drawings, or at least of a piece large enough to extend from the fioor to include the side rails of the seat. As shown in Fig. 1, the base includes the two side frames of the chair as well as the side rails of the seatframe and are connected together by crossbars B, or in any other desired manner, so as to securelyhold them in the desired positions. Below the seat-frame of the chair rockingsurfaces 0 are formed in the base by making incisions or cuts D from opposite sides extending nearly across the base, such incisions or cuts passing each other on different planes and leaving open spaces widest at the side and gradually diminishing to a point at or near the center of oscillation.
In Fig. 1 I have represented two incisions or cuts in the front and three in the rear, although any desired number may be employed. The wedge-shaped spaces formed by the incisions or cuts leave portions of the wood, which form the rocking-surfaces C. The incisions or cuts extend from the front and rear, respectively, beyond the center of oscillation on different planes, though the Wedge-shaped portions of the incisions or cuts, when the chair is in its normal position, stop short of the center of oscillation, so that the rockingsurfaces will contact with each other atthe center of oscillation. As the chair is rocked backward or forward the incisions or cuts will open and close, respectively, thus limiting the extent of oscillation. It will be understood that the incisions or cuts will run with the grain of the wood and that the pieces 0, forming the rocking-surfaces, will contain more or less resiliency as the rocking motion of the chair will tend to bend them, thus causing them to operate as springs for restoring the chair when undisturbed to its normal position.
In Fig. 4 I have shown the arrangement somewhat modified in form. The rockingsurfaces 0 and the spaces D are first formed of a separate piece of wood or other material and then fastened to the platform-rails and the seat portion of the chair by screws E or other convenient means. It is obvious, however, that the rails forming the rocking-surfaces 0 may be made integral with either the seat or platform and then fastened to the other, instead of being made separate from both. In Fig. 5 I have shown the same arrangement except that the rails forming the rocking-surfaces are all formed of different pieces of wood or other suitable material and then fastened together at the proper ends by glue, screws, rivets, or other means, so as to securely fasten them together, after which they are attached to the upper and lower portions of the chair.
The advantage of making the rockers of separate pieces from that composing the chairframe is that wood of greater resiliency may be employed where desired for that particular portion of the frame than for the rest, which will enable me to use wood of superior quality in that particular portion of the frame.
IVhere the rocking-surfaces are made of a separate portion, the base-rails, as distinctive parts, may be dispensed with and the bottom one of the pieces forming the rocking-surfaces permitted to rest directly on the floor or on casters, if they should be desired.
I have described my invention in connection with a rocking-chair, but I do not mean to confine myself to a chair technically, as my invention may be applied to cradles and other articles in which a rocking motion is desired. 1 have, however, for convenience used the term chair in my specification and claims to include chairs and other articles to which a rocking motion is to be imparted.
My improvements are intended as being applicable to rocking-chairs as contradistinguished from tilting-chairs in that the rocking-surfaces of my invention form a continuous changing fulcrum, While tilting-chairs are understood as having one or more points which act as positive fulcrum-points and do not give the easy gradual rocking motion of a rocking-chair with its constantly and continuously changing fulcrum.
That I regard as new, and desire to secure by Letters Patent, is-
1. In rocking-chairs, the combination of a chair-frame, and contacting rocking-surfaces comprising a number of strips parallel with the side of the frame having Wedge-shaped spaces between their ends, substantially as described.
2. In rocking-chairs, the combination of a chair-frame,contacting rocking-surfaces comprising a number of strips parallel with the side of the frame having Wedge-shaped spaces between their ends, and base-rails, substantially as described.
3. In rocking-chairs, the combination of a chair-frame, base-rails, contacting rockingsurfaces comprising a number of strips parallel with the side of the frame having wedgeshaped spaces between their ends arranged between the chair-frame and the base-rails, and means for securing the parts together, substantially as described.
VILLIAM I. BUNKER.
lVitnesses:
THOMAS F. SHERIDAN, SAMUEL E. HIBBEN.