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Publication numberUS316230 A
Publication typeGrant
Publication dateApr 21, 1885
Filing dateFeb 9, 1885
Publication numberUS 316230 A, US 316230A, US-A-316230, US316230 A, US316230A
InventorsRoland L. Brewer
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Roland l
US 316230 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)


(No Model.)

N'0.'316,Z30. Patented Apr. 21, 1885 W Q a v NITED STATES" PATENT JFFICE.



SPECIFICATION forming part of Letters Patent No. 316,230, dated April 21, 1885.,

I Application filed February 9, 1885. (No model.)

To all whom it may concern:

Be it known that I, ROLAND L. BREWER, of Meriden, in the county of New Haven and State of Connecticut, have invented a new Improvement in Extension Chandeliers; and I do hereby declare the following, when taken in connection with accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, in-

Figure 1, a vertical sectional side view showing the clamping devices in their contracted condition; Fig. 2, the same, showing the clamping devices thrown laterally outward to produce the clamping effect; Fig. 3, a transverse section on line w m.

This invention relates to an improvement in the clamping device for that class of lampfixtures which are constructed to be suspended from the cei1ingsuch as chandeliers and other hanging lampsand made adjustable to different elevations, and particularly to such as are constructed with a central telescopic tube or rod composed of a stationary part fixed to the ceiling and a movable part adjustable on the stationary part, the said movable part carrying the lamp-supports below. This class of extension fixtures require a clamping device between the outer and inner portions of the telescopic tube, whereby the adjustable portion maybe held at any desired point, and from which it may be rereleased when movement or adjustment of the fixture is desirable.

My invention is an improvement on the invention described in Letters Patent No. 288,852, granted to the assignees in this application November 20, 1883. In that inven-' tion the clamping device consists of two wedge-shaped blocks arranged in the inner movable tube and through openings therein, the incline of the said wedge-pieces being in the opposite directionthat is, upwardand outwardthe two supported the one upon the other, with a pin or stud diametrically through the inner tube and between the wedges, and whereby the drawing upon one wedge will cause a like movement of the other wedge in the same direction. The two bearing upon opposite sides of the said stud will be forced outward through the openings in the inner tube against the inside of the outer tube and so as to form a clamp therein. The principal object in that invention was to produce the clamping without employing the inner tube itself as one of the clamping-surfaces. The object was accomplished; but considerable difficulty is found in assembling the parts, and, practically, a difficulty arises from the liability of the wedges to set between the pin and the respective sides of the inner tube so as to interfere materiallywith adjustment. The object of my invention is to overcome these difficulties and dispense with the pin or stud between the wedges; and it consists in constructing the two wedges with their incline in the same directionthat is, upward and toward the same side of the tubes-one adapted at its upper end to be connected with a lifting device above, and at its other end to be connected to an adjusting device below, the second wedge supported in an opening in the inner tube, and so that the two wedges will be moved laterally outward by the upward movement of the one and permitted to move inward by the descent of the same one, and as more fully hereinafter described.

A represents the outer tube, which is secured to the ceiling above in the usual mauner; B, the inner tube, which carries the lamp supports or arms below, also in the usual manner. Through one side of the inner tube an opening, a, is made, and through which one part, C, of the clamp is arranged. The opening a is substantially the same length as the part C of the clamp, so that the said part C will rest therein without longitudinal movement, but yet free for movement laterally. D is the other part of the clamp, which operates through an opening, I), in the opposite side of the inner tube to the opening a. The opening 1) is considerably longer than the part D of the clamp, and so that the said part D may extend through that opening and be free for both longitudinal and lateral movement. The adjacent surfaces of the two clamps areinclined upward and away from that side of the tube in which the clamping-piece C is arranged. The upper end of the clamping-piece D is con- ICO structed to be attached to the suspending-chain E in the usual manner, and so that the adjustable part of the chandelier will be held suspended through the piece D in the usual manner for this class of clamping devices, and so that when the adjustable part is free, so as to bring the weight upon the tube B, the movable part will descend or the wedge D ascend, as the case may be, until by the combined inclination of the two clamping-pieces G D they have been forced through their respective openings in the inner tube to bear so hard against the inside of the outer tube as to create such a friction between the two as will support the adjust-able part of the fixture, the adj ust able part of the fixture hanging upon the piece 0, as seen in Fig. 2.

To relieve the clamp so that the fixture may be adjusted to different elevations, a chain or cord, F, is attached to the lower end of the clamping-piece D, and extends down through the movable part of the fixture to a suitable handle, d, and so that when a person desires to adjust the fixture they place the thumb of one hand upon thelower extremity of the fix- ,ture, and with two fingers on the handle (1 pull downward, which causes a corresponding up ward pressure on the inner tube and a downward pull upon the clamping device, so that either the inner tube is raised or the clamping-piece D pulled down, or both, into the position seen in Fig. 1. This operation permits the clamping-pieces to move inward away from forcible contact with the inner surface of the outer tube, and so that the fixture may be adjusted to the desired elevation. Then when the hand is removed from the handle d the parts are left free, so that the clamp D may be drawn upward or the inner tube descend until the two clamping-pieces shall have been again forced outward by the inclination of their respective surfaces to produce a clamping effect between the two tubes.

By this construction all frictional contact between the inner and outer tubes is avoided, the clamping being produced solely by the two clamping-pieces and the inner surface of the outer tube, thereby overcoming the objections to the Wedge-like clamping device when applied to force the inner tube against the inner surface of the outer tube and make the frictional contact directly between the two tubes, and I also avoid the use of the pin in the patent before referred to and the difliculties incident to that construction.

From the foregoing it will be understood that I do not claim, broadly, a wedge-like clamp as a device to engage the adjustable part of a chandelier with the stationary part, nor do I wish to be understood as claiming, broad- 1y, a pair of clamping-pieces arranged in the inner tube, and so as to be forced readily into contact with the inner surface of the outer tube; but

What I do claim is In an extension-lamp fixture, the combination ofan outer tube and an inner tube arranged telescopically, the one staiionary and the other movable, said inner tube arranged with openings a b,diametrically opposite each other, and the clamping-pieces O D, their adjacent faces alike inclined upward and toward the same side, the said piece 0 arranged in one of the said openings in the inner tube and supported against longitudinal movement, but free for lateral movement, the other arranged through the opening in the opposite side, but free for longitudinal movement independent of the inner tube, the said piece D adapted to be connected with the lifting device above and with a connection from the said piece D downward, substantially as and for the purpose described.




Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4059934 *Mar 18, 1977Nov 29, 1977Senoh Kabushiki KaishaArrangement for fastening an upstanding post to a floorboard
Cooperative ClassificationA61M5/1415