A device which is intended to be fitted to an armchair or like article

Abstract: A device which is intended to be fitted to an armchair or like article having at least three legs for the purpose of converting the same to a swivel armchair. The device includes at least three horizontal arms (4, 5), a base (1), which is intended to rest on a floor surface and which includes or has fitted thereto a shaft (3) around which the arms are journalled for horizontal rotational movement, and further comprises roller means (8) fitted to the arms and resting against the base, and carrier means (11) fitted to the arms an functioning to support the legs of the armchair.

Description: Technical Field The present invention relates to a device which is intended to be fitted to an armchair or like article for the purpose of converting it to a swivel armchair, as defined in the preamble of claim 1. Background Art The swivel armchairs which are presently available on the market are encumbered with certain drawbacks. For example, the general appearance of such armchairs does not match the appearance of conventional suites of furniture and the chairs also require a large amount of space for transportation and storage purposes. Furthermore, the swivel mechanism of the swivel armchair is an integral part of the chair and must be scrapped together with remaining chair parts when these become worn. DE-A-820 475 discloses a device which is intended to be fitted to an armchair for the purpose of converting the armchair to a swivel armchair, wherein the device includes chair support means, a base which is intended to rest on a floor surface and which includes or has fitted thereto a shaft on which the said means are journalled for horizontal rotary movement, roller means mounted on said means and in abutment with said base, and carrier means mounted on said means and supporting the legs of the armchair. The device of DE-A-820 475 can not be used for chairs having four legs, nor for chairs having different sizes. It is expensive to manufacture due to its complicated design. FR-A-1 590 704 discloses a device which is intended to be fitted to an armchair, having four legs, for the purpose of converting the armchair to a swivel armchair. The device includes chair support means including four arms individually swingable and horizontally adjustable about four axes on a plate resting on the floor. Each arm has mounted thereon a carrier means for each chair leg and a ball rolling on the floor. The arms of the device of FR-A-1 590 704 can be moved uncontrollable and independent of each other not only radially but also circumferentially which makes the device instable. The rotary motion of the balls may be difficult to perform on soft floor surfaces and the balls may cause damages on sensitive floors. The Object of the Invention and the Primary Characteristic Features Thereof The object of the present invention is to eliminate the aforesaid drawbacks and to provide a device which can be fitted to a conventional or standard armchair such as to convert the armchair to a swivel armchair without appreciably changing its original appearance. The device requires only a small transportation and storage space and can be switched to a new armchair when the old armchair is worn out. The device can be used for four-leg chairs having different sizes and consists of few and simple details easy to assemble and manufacture. The device is stable and can be used on any floor without damaging it. The new and important features of the device according to the invention are defined in the characterizing part of the main claim. Brief Description of the Drawings Figure 1 is a schematic view of the inventive device, seen from above; Figure 2 is a sectional view taken on the line A-A in Figure 1; and Figure 3 is a schematic view of a modified part of the inventive device, seen from above. Description of Preferred Embodiment A steel plate 2 is adhesively bonded concentrically to a larger circular plate 1 made of hardened glass or plastic. A steel shaft 3 is welded to the centre of the steel plate so as to extend vertically therefrom. Mounted for rotation on the shaft 3 are four arms, which comprise two arm-pairs, each in the form of mutually crossing tubular members 4 and 5 and each of which can be rotated horizontally about its repective centre point, at which through-passing holes have been drilled for accommodating the shaft 3. The tubular members are held on the shaft by means of a cotter pin 7. The centre part of the tubular member 5 has been removed and replaced with two flat plates 6 welded to the top and bottom sides of the tubular member, so that the two tubular members will lie in one and the same plane. The length of the piece of tubular member removed is slightly longer than the outer diameters of the tubular members 4 and 5, therewith enabling the angle between the tubular members to be varied from about 60° to about 120°, which is necessary in order for the inventive device to be fitted to different armchairs. Fitted to the outer ends of the tubular members are four rollers, such as ball bearings 8, which are mounted such as to roll against the plate 1 when the cruciform tubular members are rotated around the shaft. In order to enable the device to be fitted to different armchairs, it is also necessary to be able to adjust the lengths of the tubular members, in addition to being able to adjust the angle between said members. This has been made possible with the aid of telescopic tubes 9 which can be displaced axially in the tubular members. The telescopic tubes have welded to the outer ends thereof carrier means in the form of angle irons 11 provided with holes 12 to enable the angle irons to be secured to the undersurface of the legs of the armchair, which are therewith fixated at a level of some centimeters above the level of the floor on which the plate 1 rests. Subsequent to having secured the angle irons, stop screws 10 are tightened so as to lock the telescopic tubes and to render the legs of the armchair stable. Figure 3 illustrates an alternative embodiment, in which the plate 1 is replaced by an annular 13 having spokes 14 which accommodate the shaft 3 at their radially inner ends.

Claims: A device which is intended to be fitted to an armchair or like article for the purpose of converting it to a swivel armchair, including chair support means (4-11) and a base (1) which is intended to rest on a floor surface and which includes or has fitted thereto a shaft (3) on which the support means are journalled for rotary movement in the horizontal plane, characterized in that the support means (4-11) includes two horizontally extending and mutually crossing telescopic arms (4, 5) which are rotatable around a common central axis (3) and which have mounted thereon carrier means (11) supporting four legs of the armchair, said arms being so mounted and constructed that the angle between and the radial positions of said arms is adjustable, and that the arms have mounted thereon roller means (8) which are in the form of bearings surrounding the arms, and which are free to roll on the base (1). A device according to claim 1, characterized in that the carrier means (11) are located radially outside the roller means. A device according to claim 1 or 2, characterized in that the roller means (8) have the form of ball bearings.

Inventors: ROENBLOM CLAES, ROENBLOM, CLAES, Rönblom, Claes
Applicants: ROENBLOM CLAES, ROENBLOM, CLAES
Application year: 1991
Main classification: A47C3
IPC codes: A47C3