US1375394A - Ball-caster - Google Patents

Description

T, KELLY. BALL CASTER.

APPLICATION FILEDAPR-Z, I920. 1

1,375,394. Patented A r.- 19, 1921 1 7 3 ER v 6 2 4 INVENTOR Tkamas K6 WITNESSES warren stares EFEQE THOMAS KELLY, 0F POULTON-W'ALLASEY, ENGLAND.

BALL-CASHIER.

Application filed April 2, 1920. Serial No. 370,776.

To all whom it may concern:

Be it known that I, THOMAS KELLY, a subkect of the King of Great Britain, residing at oulton-Wallasey, in the county of Cheshire, Kingdom of England, have invented a new and useful Ball-(Jaster, of which the following is a specification.

his invention relates to ball casters.

The object is to provide a caster of the ball-bearing type which supports the entire load of a piece of furniture or other article upon which the device may be used, through the medium of a single relatively large, ball contacting with the floor or other surface and freely rotatable in any direction, the said ball being confined in a rotatable cage carrying a series of small balls interposed between the same and the stationary ball race carried by the article of furniture.

Another object is to provide a device of this character which, when manufactured in quantities, may be produced at a low cost and, by reason of the simplicity of its construction, may be readily applied to the-leg of the furniture or other article, without weakening or detracting from the appearance of the same, and which will reduce to a minimum the liability of breakage or derangement while under the great strain to which such devices are subjected. A full and complete understanding of the invention may be obtained from a consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding, however, that the invention is not confined to any strict conformity with the showing of the drawing, but may be changed and modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims. 7

In the drawing, in which similar reference characters designate corresponding parts throughout the several figures- Figure 1 is a side elevation of the lower portion of the leg of an article of furniture having the improved ball caster applied thereto;

Fig. 2 is a vertical sectional view of the same;

I Fig. 3 is an inverted plan view of the de- Fig. 4 is an inverted plan view of the ball race member;

Fig. 5 is an inverted plan view of the ball ca e member.

eferrin to the drawing, there is illustrated in F gs. 1 and 2 the lower portion of a leg 1, WlllCll may be that of any article of furniture, though the deviceis equally well adapted for use in any location where it is desired to reduce to a minimum the friction between two relatively movable bodies. At the lower end of said leg, which is shown as being round in cross section, there is secured a hardmetal ball race or track member 2, which is also round and preferably of the same diameter asthe leg 1, though this of course is not Obligatory. The ball race or track 2 comprises a flat disk or plate 3 surrounded by a marginal, depending flange 4, and having at its center, a straight bore or passageway 5 and a series of bores or passageways 6 arranged around the same, equid stant therefrom and spaced an-equal distance apart. The latter bores are countersunk on the inner face of the disk or plate 3 for the reception of relatively short screws 7 which are driven into the lower end of the leg 1 and serve to securely hold the ball race or track member in position thereon.

A rotatableball cage member 8, cylindri- V cal in form and of a diameter to fit freely within the depending flange 4, is also formed of steel or other hard metal, and comprises an upper disk or plate 9, flat upon its upper surface and beveled underneath being considerably thinner at the center than at the periphery thereof, the center having a countersunk bore or passageway 10. The disk or plate 9 is provided with an integral, marglnal, depending flange l1, considerably longer than the aforesaid flange 4 of the ball race member, said flange being provided with an annular groove 12 upon the inner wall thereof and near the bottom end of the same,thus providing a hollow-cup-like ball cage member closed at the top and open at the bottom and adapted to partially surround and house a relatively large steel ball 13 which is confined within the surroundin flange 11 and extends considerablyv below the lower edge thereof to rest upon the floor or other supporting surface' The disk or plate 9 of the ball cage member is provided with a series of hemi-spherical ball seats 14, preferably three in number arranged equi-distantly from the central bore or passageway 10 and an equal distance apart, as clearly shown in Fig. 5 of the V i in spaced relation to the apex thereof and drawing, the said hemi-spherical ball seats extending through the disk or plate 9 and each adapted to receive a steel ball 15 of considerably less diameter than the steel ball 13. Said balls 15 rest upon the larger ball project through the seats 1 1 su'liiciently to bear upwardly against the lowerface of the ball race plateor. disk 3, and to transmit the weight carried thereby directly upon the large ball with the minimum amount of friction, the three-point bearing thus provided, permitting of the greatest amount of freedom of the ball 13 and allowing'the article supported by the caster to be moved in any desired direction with the greatest ease. "Asplit ring 16 is adapted to be sprung i into the seat 12 ofthe flange 11 and to retain i the ball 13 in its housing, the said ring lying when the same may be forced into the seat 12,'whereupon the ring will expand and cocupythesame. It is only necessary in removing the same, to introduce a pointed implement between the ends 17 of the ring and pry one of thejends out-of the 1 groove 12, when the entire ring 16 may be removed, as will be clearly understood, by reference to "Fig. 3 ofthe drawing.-

Inassemblingthe ball bearing caster, the

ball-race or trackmember 2 is first applied to the lower end of the leg 1 by the applica- 40 V i securely hold the'member 2 in position, when {the cage member 8 is then introduced within tion of the relatively short screws 7, which the flange 4:, and a "somewhat longer screw 18 is screwed through the alined passageways 5 and 10 respectively, and into the center of l the leg along the longitudinal. axis thereof, the head of the long screw being embedded in the countersunk bore 10 and lying flush with the underface of the plate or disk9. Thesmaller balls 15 are then placed in their seats 1 1 and held therein by the larger ball "13 which is next positioned within the annular flange 11, the ring 16 being placed in the groove last to retain the parts in their proper positibn. V a

It will be noted that the ball 13 is free to rotate in any direction, the smaller balls 15 being so positioned as to take up an equal 7 amount of the weight imposed thereon.

Vl hen the leg 1 is moved laterally the ball 7 13will impinge against the inner wall of the flange 11 and, under certain conditions, will cause the latter to rotate upon its vertical axis, the longer screw 18 being screwed into the leg 1 in such manneras to permit of the ball cage 8 rotating freely thereon, which overcomes any friction which might arise if the flange 11 were not free to thus move.

From the foregoing it will be seen that a strong durable and eflicient anti-friction device has been provided for use upon the legs of furniture or for analogous purposes and that the same, by reason of the simplicity of its construction, may be cheaply manufactured, readily assembled and applied in position to give the maximum amount of delicacy orsensitiveness in its movement'and that the same is-calculated to support great weight and withstand strain, with the danger of derangement or breakage reduced to a minimum. Y i i What is claimed is i 1. A ball bearing oaster comprising an upper or ball race member comprising a flat disk or plate having a depending marginal flange, a ball cage member having its upper portion fitted withinsaid flange and comprising a flat disk or plate and a depending marginalflange, a relatively large ball arranged within the flange'of the cage member, means'for holding the ball therein, a series of small ballsrestingupon the large ball at spaced points around the top thereof, and a plurality: of ball seats provided in the disk of the cage member, said seats opening out at the top, whereby the small balls are adapted to contact'with the roll against the 'upper member;

2. A'ball bearing caster including a ball race member comprising la plate or disk with a depending marginal'flange, a ball cage member fitted within said flange, means for pi'votally mounting said ball cage member in position so that it may rotate within" said flange, said ball cage member carrying a large ball, anda plurality of small balls interposed between said large ball and the ball cage member;

8'. A ballbearing caster comprising a ballrace member adapted to besecured to the article to be supported and provided with'a depending marginal flange, a ball oage-me'mberfltting within said flange, said cage member comprising a flat disk provided with spaced hemispherical ball seats which open out through the top,'relativ'ely small balls fitting in said seats and projectingthrough I the same to bear against the ball race, a circular marginal flange depending from the r disk of the ball cage member, a relatively largeball arranged within the last-named flange and bearing upwardly against the smaller balls whereby the pressure is transmitted'to the ball race member, and means mounted on the depending marginal flange for holding. the large ball in position;

4. A ball bearing caster comprising a ball race member adapted to be secured to the article to be supported'and provided with a depending marginal flange, a circular ball cage member fitting Within said flange and held for rotation therein, said cage member comprising a disk flat on its upper face and provided with spaced hemispherical ball seats which open out through the top, relatively small balls fitting into the seats and projecting through the same to bear against the under side of the ball race, a circular marginal flange depending from the disk of the ball cage member, the disk of the cage member being of least thickness at its center, pivotal means passing through the center of the said disk for holding the same to the ball race member, the disk of the cage member being of greatest thickness Where it joins with the marginal flange, the small balls being seated intermediate the thinnest and thickest parts but equi-distant from'the pivot of the ball cage, a relatively large ball arranged Within the marginal flange of the cage member and bearing upwardly against the smaller balls, and means preventing the large ball from dropping out of the cage member.

In testimon that I claim the foregoing as my own, nature.

THOMAS KELLY.

Witnesses WILLIAM PIERCE, JAMES CHARLES MORAE.

have hereto aflixed my sigi

Images