US3374347A - Electric lamp stand - Google Patents

Description

March 19, 1968 YOU HIROSE ELECTRIC LAMP STAND 2 Sheets-Sheet l Filed Aug. 23, 1965 IN VEN TOR. )fok Hf' rafa.

March 19, 1968 lYou HIROSE 3,374,347

ELECTRIC LAMP STND Filed Aug. 23, 1965 v 2 sheets-sheer a INVENTOR. YOH- lfv United States Patent ilice 3,374,347 ELECTRIC LAMP STAND You Hirose, 24-7 3-ban-cho, Chiyoda-ku, Tokyo, Japan Filed Allg. 23, 1965, Ser. No. 481,480 2 Claims. (Cl. 24o- 52) ABSTRACT F THE DISCLOSURE A swivel arrangement including a rst member and a second member at least one of which is rotatable with reference to the other about a predetermined axis. Resilient means interposed between the members and connected therewith, such resilient means biasing the members against one yanother with a force which varies in response to relative angular displacement of said members.

The present invention relates to an electric lamp stand. An object of the present invention is to supply an electric lamp stand consisted of supporting rods in 2 legs or more and swivel joints in 2 legs or more jointing said supporting rods.

Another object of the present invention is to supply an electric lamp stand wherein a spiral spring being installed in the swivel joint jointing the supporting rods, the resilient force of the spring being changed in correspondence to the displacement of the center of gravity of the lamp stand due to the folding inclination of the supporting rods whereby the lamp stand is always maintained in stability regardless of the 4degree of inclination of the supporting rods.

Still another object of the present invention is to supply an electric lamp stand wherein the spring installed in the swivel joint is not simply to maintain the lamp stand in stability, but also, the spring being formed into a conical shape, enables one to move the illuminating body of the lamp stand to any position as desired and maintain the illuminating member in its moved position securedly by having the constructional frictional force changed in correspondence to the extent of the winding thereof.

Still another object of the present invention is to supply an electric lamp stand wherein a shade constituting the illuminating number being made freely detachably at its expanded en d, whereby the volume of the lamp stand is reduced for the convenience of packing and transportation.

Further still another object of the present invention is to supply an electric lamp stand wherein a hood in semitransparent milky white'colour for preventing the dispersion of illuminating light and softening the direct projection of the light is pressedly .attached freely detachably to the top end portion of the shade.

Further still another object of the present invention is to supply .an electric lamp stand simple in constructional form and excellent in appearance.

In view'of the objects described above and other objects that will be described hereinafter, an embodiment according to the present inventionwill be described with reference to the accompanying drawings.

In the accompanying drawings,

FIG. l yis" a side vview of an embodiment of the electric lamp stand according to the present invention, partly cut off;

FIG. 2 is an enlarged sectional view of the swivel joint of an important portion thereof;

FIG. 3 is a perspective view of the swivel joint disassembled; K

FIG. 4A is a side view of the upper half thereof of the lamp shade, and FIG. 4B is a plan view of the lower half thereof;

3,374,347 Patented MarI 19, 1968 sectioned along the line ings, numeral 1 indicates supporting rods in 2 legs or more jointed in order through swivel joints a and they are made of a hollow shape 2, through which electric codes can be inserted.

The swivel joint a is consisted of a holding member 5 in a 2-leg form in side view parallelly provided with a pair of holding disks 4 4, a rotary member 6 rotating in sliding contact with the inner side of said holding mem ber 5, and a spiral spring 7, and said holding member 5 and said rotary member 6 are securelyaiixed by a shaft 11 like a bolt and a nut inserted through a center hole 8 of said holding disks 4-4 Iand a shaft hole 10 projectinglyV provi-ded on the disk portion9 of said rotary member 6.

The rotary member 6 being made into an open portion 6 on its one side in the present case, a pair of circular spring recipient plates 13, 14, one made of iron and the other ofsteel, being tted into a step 12 formed on the inside of the opening of said open portion 6', a spring 7 is insertedly installed between said spring recipient plate 13 and one of the holding disks 4 4.

The spring 7 being made into a spiral form projecting in a conical form in side view, the outer end 7' thereof being bent in a hook form which hook is hooked to a groove 15 bored on the holding disk 4 on one side of the holding member 5, and the inner end 7 thereof being hooked to a hooking hole 16 provided on the inner side of the circular plate 9 of the rotary member 6, whereby the spring 7 is compressed to a at form. Thus, spring 7 exerts a tangential force on holding member 5 and on rotary member 6, while at the same time bearing on the plate 13 and the disk 4 to thereby exert a frictional force on the friction plate 19 as a result of the prestressing achieved by compressing of spring 7 to flat state.

Further, a step 17 being cut on both side outer periphery of the rotary member 6 so as to have the outer end bent portion of decorative covers 18-18 contacted along the holding disks 4-4 of the holding member 5 tted thereonto, and also a circular friction plate 19 being contacted along the outside of the disk 9 of the rotary member 6, is slidingly contacted with the holding disk 4 of the holding member 5 through said friction plate 19.

When the swivel joint a is to be provided at the lowermost end of the lowest supporting rod 1, as shown in FIG. 1, the holding member is provided on a supporting rod 20 which can be freely detachably inserted into an opening 22 of a lamp support element, comprising the clamp21, which can secure the lamp to a body like a desk. Irf the joint is to be provided as the junction between two of the supporting rods 1 instead, then the holding member is provided on a suporting tube 23 which can be connected with the supporting rod 1.

A projected rod 24 at the upper portion of the rotary member 6 is for connecting with the supporting rod 1.

The electric lamp stand shown in thedrawing is consisted of a pair of swivel joints a, large and small, up and down, wherein a pair of supporting rods 1, large. and small, are connected withthe swivel joints a, and to the uppermost supporting rod 1v a freely rotatable shade 25 is pivoted Land said shade 25 is so constructed as to be separable into an upper shade 25a and a lower shade 25b.

'Ihat is, the upper shade 25a being made toa thin cylindrical form expanded to a trumpetshape, a turn switch 26 for connecting to an electric circuit is provided on the top thereof, :and in the inside thereof a lamp attachment 27 being formed, the lower end thereof being expanded slightly outwardly whereby .a perpendicular ange 28 being formed, an engaging groove 29 of a U shape engaging said flange 28 being provided on the upper portion of the lower shade b and the lower shade 25b expanded to an arced shape is enabled to be connected with the upper shade, and further stopper pins 30 in a plurality being mounted on desirable positions of the engaging groove 29 whereby is enabled to be inserted into a L-shape groove 31 provided on the perpendicular ange 28 of the yupper shade 25a, whereby the upper and lower shade 25a, 25b can be engagingly connected -by having the upper and lower shades rotated.

Also, on the engaging groove 29 a slot 32 is bored along said groove whereby the effect of the dispersion of heat accumulated due to the radiation of an electric lamp is imparted thereto.

Furthermore, annular hood 34 projectingly provided with a supporting leg 33 being attached freely and detachably to the lower end opening of the lower shade 25b, whereby the softening effect of illumination by said hood 34 with a synthetic resin body of a white milky colour is intended.

In order to have the attachment of said hood 34 to the lower shade 25b bettered a cut-off portion 35 being provided on the opening of the shade 25b, whereby it is so constructed as to have the hood 34 attached in a simple manner by having the supporting leg 33 inserted in along said cut-01T portion 35.

In the accompanying drawing numeral 36 indicates an insertion through hole bored on the rotary member 6 for inserting an electric cord, numeral 37 a sidewise fallen M- shape holder of a leg supporter 21, and numeral 38 the threaded rod of the holder.

Describing the operation of the electric lamp stand according to the present invention based on the construction described above, when, in having the leg supported 21 securely set at a desired position iirst, the illuminating body is made to move to a desired position, and the supporting rods 1 are folded freely through the swivel joints a, and for the displacement of the center of gravity accompanying the fold of the supporting rods the weight balance of the structure is maintained by having the resilient force of the spiral spring 7 changed by changing the extent of its winding in proportion to the degree of inclination of the supporting rods 1, and the spring 7 changes automatically the extent of its winding in correspondence to the degree of fold of the upper and lower supporting rods 1 connected through the swivel joints a and the degree of inclination of the supporting rods 1 to the leg supporter 21, in other words, the more remote from and 'lower than the position of the leg supporter 21 the illuminating position of the shade 25 or the smaller the degree of fold of the upper and lower supporting rods 1, the tension of the spring 7 gets greater whereby the movement of the center of gravity of the structure or the increase of load on the leg supporter 21 due to the displacement of the shade 25 are reduced and absorbed.

The swivel joint a being inserted with a friction plate 19 and the spring 7 between the holding member 5 and the rotary member thereof so that the originally conical spring 7 is axially compressed and thereby prestressed, energy storage of the spring resulting from increased winding of the same in a sense tightening it, causes concomitant stifening of the individual convolutions so that the biasing force of the spring in axial direction of the latter is increased thereby, as a result thereof the frictional force on the friction plate 19 is increased more and more whereby a proper frictional force is given thereto at the time of its rotation, and in consequence the CFI frictional force thereof in conjunction with the tension of the spring balances the weight of the shade 25 and enables the latter to maintain its state securely at any desired inclined position.

In addition, since the supporter 5 of the swivel joint a located at the lowest position is especially insertedly supported loosely in the hole 22 of the leg supporter 21, the shade 25 can be rotated to any direction of 360 degrees.

When a lamp is to be lighted, if a turn switch 26 is operated, the light of the lamp is projected downwardly through the opening of the lower shade 25b, and especially the hood 34, reducing the light to the outside of the shade, is effective for softening the light and also concentrating the light, and since a slot 32 is bored on the engaging groove 29, it acts to reduce heat accumulation accompanying the lighting of a long duration in dispersing the heat.

The shade 25 being enabled to be separated into the upper and lower shade 25a, 25b and also the hood 34 being enabled to be parted from the lower shade 25b whereby the shade has a characteristic of convenience in the packing and transportation thereof.

The electric lamp stand according to the present nvention being consisted of the supporting rods in 2 legs or more and the swivel joints in 2 legs or more as described hereinabove, its form can significantly be simplified and in addition the shade thereof being enabled to be inclined to fany desired position by the tension and frictional force of the spring installed in said swivel joint, the handling of the lamp stand is very simple and is easy in operation.

What is described hereinabove is only an embodiment of the electric lamp stand according to the present invention, and the present invention is not restricted by the said embodiment by any means and is applicable within the whole scope of the present invention.

What is claimed is:

1. A swivel arrangement, particularly for lighting fixtures, comprising the combination of a first member including a -bifurcated element having two spaced parallel portions, and a second member received between said portions of said bifurcated element, at least one of said members being rotatable with reference to the other member about a predetermined axis; and resilient means in form of a conically tapering helical torsion spring interposed in axially prestressed state between, and having opposite axial ends respectively connected to said second member and one of said portions of said first member, said torsion spring urging the other portion of said bifurcated element and said second member toward one another with increasing force in response to relative angular displacement of said members about said axis in one direction of rotation, and with concomitant variation in the torsional force of said spring.

2. An arrangement as defined in claim 1, and further comprising abutment plates interposed between said other portion of the first member and said second member on the one hand, and lbetween said second member and said spring on the other hand.

References Cited UNITED STATES PATENTS 1,349,241 8/1920 Walsh 240-78 2,233,300 2/ 1941 Trythall 240--81 2,395,178 2/ 1946 Fiori 24U-,8l 2,472,624 6/ 1949 Schwartz 240-81 2,666,844 1/1954 Beck 240--78 2,673,291 3/1954 Moss 240-78 FOREIGN PATENTS 188,476 3/ 1964 Sweden.

NORTON ANSHER, Primary Examiner.

R. M. SHEER, W. M. FRYE, Assistant Examiners

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