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Publication numberUS612792 A
Publication typeGrant
Publication dateOct 18, 1898
Filing dateMay 2, 1898
Publication numberUS 612792 A, US 612792A, US-A-612792, US612792 A, US612792A
InventorsElwin L. Thompson
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
l thompson
US 612792 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

No. 612,792. Patented Oct. l8, I898. E. L. THOMPSON;


Application filed may 2, 1898.)

(No Model.)

2 Sheets-Sheet I.

No. 6l2,792. Patented Oct. l8, I898. E. L. THOMPSON.


(Application filed May 2, l898 Modem 2 Sheefs-Sheet 2.

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SPECIFICATION forming part of Letters Patent No. 612,792, dated October 18, 1898.

Application filed May 2, 1898. Serial No. 679,429. (No model.)

To aZZ whom it may concern.-

Be it known that I, ELWIN L. THOMPSON, of Baldwinville, county of \Vorcester, State of Massachusetts, have invented an Improvement in Convertible Chairs, of which the following description, in connection with the accompanying drawings, is a specification, like letters and figures on the drawings representing like parts.

This invention relates to that type of chair constructed and arranged to be readily converted at will into a high or low chair or carriage; and my present invention has for its object the production of an improved and simplified chair of such type of increased strength and durability.

Figure 1, in side elevation, represents in its high position a chair embodying my invention. Fig. 2 is a like view of the chair in its lowest position. Fig. 3 is a rear elevation of the chair, viewing Fig. 1. Fig. 4 is a sectional View taken on the line m as, Fig. 1, looking down, the seat being partly broken out; and Fig. 5 is a detail of a modified form of locking device, to be described.

The chair-body A is provided with the two pairs of crossed legs a b, the former pivotally connected with the body at their upper ends at a and pivoted at a to a cross-bar 5, to which the legs 17 are also pivoted, the lower ends of said legs being herein shown as provided with wheels w. The legs I) are pivotally connected by links b, attached near their upper ends, to the body A, and when the chair is lowered, as in Fig. 2, the body is retained in proper position by the engagement of the legs a above their fulcrum-point a with a stop-bar 6, connecting the legs 12.

Means are provided to lock the chair in its highest position, and I have herein shown two forms of locking means, that in Figs. 1 to 4, inclusive, comprising a frame d, fulcrumed at cZ beneath the seat, the rear portion of said frame projecting beyond the seat to form an actuating handle or portion (1.

One or more springs s tend to maintain the notched or hooked ends d 'of the frame 01 in engagement with projections or lugs b on the upper ends of the legs I), so that by preventing separation of the upper ends of the two pairs of legs the chair is maintained in its high position. By depressing the handpiece (1 the hooks d are disengaged from the lugs b so that the legs can spread and lower the chair-body into position Fig. 2.

In order to provide a push bar or handle F for the chair when the same is lowered, I have herein shown two arms f, rigidly connected at their upper ends by a cross-bar f and pivotally connected at their lower ends to the legs I) at f. When the chair is in its high position, the handle F should be drawn up as closely as possible to the chair-back to be out of the way, and when the chair is lowered the handle should then be in convenient position to be grasped by the hands to propel the chair-carriage. To effect this result, I provide one or more guides, which are fixed to the chair-body and have a sliding engagement with the handle, so that when the guides approach or recede from the pivotal connection of the handle and chair-legs the handle will be swung outward or drawn in toward the back of the chair, respectively. I have herein shown the guides as metal brackets g, secured to the back of the chair-seat and provided with ears g, which enter longitudinal recesses, grooves, or ways f on the arms f, the length of the ways or grooves permitting the requisite travel of the guides. The ears 9 are shown as oppositely turned to enter the ways or grooves formed on the inner sides of the arms f, so that the guides retain the handle in position at all times.

In Fig. 5 I have shown a modified form of locking device, the guide g g being shown as cooperating with the arm f, as before. On the said arm, near the upper end of the groove f, I pivotally mount at 78 a dog 72., having its upper end laterally extended and bent to form an car It adjacent the inner side of the arm f, a spring 5 normally holding the dog in the position shown in Fig. 5, with a locking-shoulder 7L2 beneath the guide g. While in this position, the dog locks the chair-body in raised position; but if theoperator presses the ear h toward the arm f the shoulder 72, will be withdrawn from beneath the guide, permitting the chair to be lowered. When the chair is raised, the spring 8 permits the I claim, and desire to secure by Letters Patent, is-

1. In a chair of the class described, the vertically-adj ustable chair-body, its legs, a pushhandle pivoted at its lower end to the chairlegs, and one or more guides rigidly fixed on the chair-body and in sliding engagement with the push-handle, substantially as described.

2. In a chair of the class described, the vertically-adj ustable chair-body, its legs, a pushhandle pivoted at its lower end to the chairlegs and provided with longitudinal ways, and one or more guides rigidly fixed on the chair-body and in sliding engagement with the said ways, to control the position of the handle when the chair is raised or lowered, substantially as described.

3. A convertible chair, comprising a vertically-adjustable chair-body, pivotally connected and crossed front and rear legs therefor, means. to lock the chair in raised position, a handle pivoted to the rear legs of the chair, and one or more guides in sliding engagement with the handle and rigidly secured to the chair-body, substantially as described.

4. A convertible chair comprising a-vertically-adjustable chair-body, pivotally connected and crossed front and rear legs, springcontrolled locking means to lock the body and legs from relative movement, a handle pivotally connected with the rear legs, and a connection between the chair-body and handle, in sliding engagement with the latter, substantially as described.

5. In a chair of the class described, the body, its legs, a push-handle pivoted to the chair-legs and provided with longitudinal grooves, and guides rigidly secured to the chair-body and having outwardly-turned lips toenter said grooves, to thereby control the position of the handle at all times, substantially as described.

6. A convertible chair comprising a body, pivotally connected and crossed front and rear legs and locking means, comprising a rocking frame pivoted beneath and upon the body and adapted to engage lugs on the upper ends of one pair of the legs, and a handpiece by which the frame may be moved extended between the upper ends of the other pair of legs, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.


Witnesses: H


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2528452 *May 27, 1946Oct 31, 1950Edward M RileyCombined high chair and stroller
US4125286 *Jul 2, 1971Nov 14, 1978Redel Ray HConvertible chair
US7314248 *Mar 3, 2005Jan 1, 2008Robert Alan MabonPortable workstation
US20060197362 *Mar 3, 2005Sep 7, 2006Mabon Robert APortable workstation
Cooperative ClassificationB60B33/06