US 2659559 A
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Nov. 17, 1953 L. J. DU MAIS PICTURE SCREEN STAND 2 Sheets-Sheet 1 Filed June 19, 1951 I a" INVENTOR.
I ATT'YS LEO J.DUMAIS BY Nov. 17, 1953 1.. J. DU MAIS 2,659,559
PICTURE SCREEN STAND Filed June 19, 1951 2 Sheets-Sheet 2 INVENTOR." LEO J.DuMAss ATT'YS Patented Nov. 17, 1953 =;1TED STATES PATENT OFF-ICE PICTURE SCREEN "STAND Leo .zLBwMais, -Chicago, 111., assignor to Da-Lite Screen Company, vInc., .Chioago, 111., a \corpo- .rationlo'flllinois ApplicationJune I9, 1951,"Se1 ia3l No. 232,407
This invention relates to stands for screens upon which pictures are projected and hasparticular reference to devices :for controlling the disposition the tripod legs upon which the stand is 'inounted.
The objects of this invention are to :provide improved means fol-securing the tripod legs rn'a retracted in which theylie along an close to the standard for compact disposition when 'notin use; and to provide improvedimeans for causing the tripod legstoswing apart to their stand-supportingjpositicn.
A further object of this invention to tprovide an improved relation between the screen housing, the standard, its extension rod and'the legs of the tripod, whereby these :parts are firmly act relation to @each other for releaeedior oonvenient erectionof thescreen and "its stand upon the release or a single :latch member.
specific embodiment of this invention is shown in the acoornpanyi' g drawings in which:
.liigure 1 is a perspective view of the screen and s stand which the parts are shown in the positions which they occupy just prior to collapsing the legs of the tripod into their retracted position with respect to the standard.
Fig. 2 is a fagmentary detail, in side elevation, of parts of the device illustrating the manner in which the tripod legs are held in compact relation to the standard.
Fig. 3 is a similar fragmentary view, partly .sectional, showing the structure and arrangement of the latching devices.
Fig. 4 is a transverse section of the extension rod latch taken on the line 4li of Fig. 3.
Fig. 5 is a transverse section takenon the line 5-5 .of .Fig. 3.
.Fig. 6 is a perspective view of the member which serves as a latch for holding the legs in their retracted relation to the standard and provides cam tracks by means of which the tripod legs are forced apart to their positions of loadsupporting relation to the standard.
Fig. 7 is a detail, in perspective, of the capon the lower end of the. extension rod.
Fig. 8 is a detail of a split washer that serves as an abutment for the compression spring that releases the extension rod from its looking ongagement with the screen housing and also furnishes the power which forces the tripod legs apart.
Fig. 9 isa detail, in perspective, of the cap on the lower .end of thestandard.
In the dorm shown, the tripod standard and screen housing are of well-known construction with :but'slight modification for the accommodaticn of the latching devices of the present invention.
The main standard to is a tube having an extension rod H telescoping therewith and being guided in its vertical movement by cap 12 on the upper end of the standard leand'a cap it .on the lower end of the extension rod which is loosely slidalole within the inner walls of the tube It.
A handle it is carried by a bracket 15011 the standard 19, to which bracket the screen housing it is pivotally mounted :at 47 so as 'to swing from the position :of parallelism with the standard iifirin'which it is shown in the drawings, to apositionat right angles to the standard. A cap 28 at the upper end iof the extension rod ill has an upturned hook 13, upon which the hail of the screen be hung, and has a dependingsfinger or ,prongrlil for engaging a socketin the cap 2:! on the .end of the screen housing It. A latch member 2,2 is mounted on the standard Ii! and engages the extension rod H for locking the extension rod 'and housing E6 in the positions in which theylare shownlin Figs. 1 and 2.
In the form shown, the latch member .22 :is in thelform of a looped band that embraces the cap :12 and has spaced parallel side portions guided for transverse movement on the cap by lugs v2%. The overlapped ends of the band that forms the latch member 22 are "secured together by a rivet 24 which :is extended to form a latch lug 25 adapted toengage an aperture in the adjacent wall of the tube 44. iris will be understood, there maybesa numberof such apertures spaced apart along the rod :H appropriately located for enegagement with the latch lug 12.5 :in the position which thepartsare=showninlthe drawings and in various other :positions to which the extension rod .may be desirably withdrawn from the standard It for appropriatesupportof Zthescreen, A helical compression :spring :2 6 normally urges the latch lug 25 into engagement with the extension rod :Ill and yields to permit the latch rlug to be withdrawn from such engagement by pressure .uponthelatch member 2-2 the direction'of'the .arrowsz'l of Figs..1:and 2.
The standard I0 is "supported .in its upright position, as shown .in Fig. =1, by tripod vlegs :28 that are pivotally mounted on an upper bracket member '29 that :is :loosely slidahle along the standard 1-0 and -th'at :are :connected by spreader =lin'ks 30 tosaflbracketzal ithatis fixed at the lower end of the standard 1-0 by means or 'acap "plate 32 and screw 33. As indicated in the drawings, the legs 28 and the spreader links 30 are of channel shape in cross section. The bracket member 29 is provided with a finger-hold 34 whereby it may be lifted along the standard I to collapse the legs 28 of the tripod into a position in which they lie close to and parallel with the standard H).
The mechanism for holding the tripod legs in their collapsed position and releasing them from this position and projecting them outward toward their load-supporting position comprises a stem 35 which is of rectangular or other prismatic cross section so as to be axially but non-rotatably slidable in the aperture 36 in the cap 32. The stem 35 is surrounded by a helical compression spring 31 that bears between the cap 32 and a projecting abutment shoulder 33 at the upper end of the stem 35. This shoulder is in the form of a split washer 38 seated in a groove 39. The cap l3 at the lower end of the extension rod H is apertured so as to clear the head 40 of the stem 35, and to rest firmly on the washer 38; but is freely movable upwardly away from the stem 35.
- Rigidly fixed on the lower end of the stem 35 by a rivet shank 4| is a latch member 42, which has spider arms positioned to coast with the tripod legs. To this end the member 42 has a hexagonal aperture 43 snugly fitting the rivet shank 4| so that upon upsetting the rivet shank to form a head 44, the member 42 will be rigidly fixed on the lower end of the stem 35 with its various parts in proper location for coaction with the legs of the tripod, as will hereinafter appear.
Each of the tripod legs 28 has a rivet 45 extending across its channel and serving as a keeper lug positioned to coact with one of the latch tongues 46 on the latch member 42, when the tripod legs 28 are in the retracted position indicated in Figs. 2 and 3 and the stem is in its lowermost position, due to the compression of the spring 31. When the parts are in this position, the keeper lugs 45 will be releasably held against displacement from the member 42 by detent shoulders 41 on the respective yielding spring latch tongues 45. When the extension rod H is held in the depressed position in which it is shown in Figs. 1, 2 and 3 by means of the latch 22, the spring 31 will be compressed and the member 42 will be in position for engagement with the keeper lugs 45 of the tripod legs.
In addition to having detent shoulders 41, the latch member 42 is provided with arms 48 which stand in planes at right angles to the plane of the body portion of the member 42 and have inclined edges 49 that serve as cam tracks for engaging the shoulders provided by the respective keeper lugs 45 and forcing the tripod legs 28 apart when the member 42 is lifted by the expansion of the spring 31 upon release of the extension rod H from the latch 22.
The operation of the device shown lows:
To bring the parts to their collapsed position for storage, after the device has once been set up and is standing on its tripod, the screen housing I is first turned on its axis [1 so as to lie along the standard I0, then the cap it is depressed by the operator from its normal position, indicated by dotted lines in Fig. 1, to the position shown by full lines in Fig. 1. The finger will then have become seated in the screen housing and the extension rod will have been depressed to allow the latch lug to fall into the corresponding is as folaperture in the extension rod II. The depression of the rod II will have retractively compressed and energized the spring 31 and will have lowered the latch member 42 to position for coaction with the keeper lugs 45 on the tripod legs. Then by lifting the finger-hold 34, the operator causes the legs 28 of the tripod to swing to their collapsed position with the keeper lugs 45 engaged behind the shoulders 41 of the spring tongues 46. The device is now ready for storage or convenient transportation.
To set the device up for use, the operator holds it by the handle I4 with the standard ID in a vertical position and presses upon the latch member 22. Upon release of the extension rod l I by this latch member, the spring 31 expands and lifts the extension rod ll sufficiently to carry the lug 20 out of engagement with the screen housing. The expansion of the spring 31 causes the stem to be projected upwardly rapidly until stopped by the engagement of the member 42 with the cap 32.
Due to this sudden lifting of the member 42, the detent shoulders 41 release the keeper lugs and the cam tracks 49, running on the keeper lugs 45, throw the legs 28 outward with sufiicient force to carry them to or close to their loadsupporting position, whereupon the device can be set upon the floor, the screen housing turned to its horizontal position and the screen attached to the hook I9. Thereupon the extension rod can be lifted to any desirable height and locked in such place by engagement of the latch lug 25 with an appropriate aperture in the extension rod H.
Although but one specific embodiment of this invention is herein shown and described, it is understood that numerous details of the structure shown may be altered or omitted without departing from the spirit of the invention as defined by the following claims.
l. A screen stand, comprising a tubular standard, an extension rod telescoping into said standard, a sleeve slidable along said standard, a plurality of legs located for supporting said standard in an upright position and pivoted on said sleeve, a bracket on said standard spaced from said sleeve, links connecting said legs to said bracket for swinging said legs toward and away from said standard through sliding movement of said sleeve, a stem telescopically slidable in the end of said standard adjacent to said legs, a compression spring normally urging said stem inward along said standard, said extension rod being slidable into position to depress said stem and compress said spring, latch means acting between said standard and extension rod for holding said springs compressed, shoulders on said legs, and cam means on said stem adapted to bear on said shoulders to spread the legs apart through the expansion of said springs upon the release of said latch means.
2. A screen stand, comprising a tubular standard, a pair of bracket members, one being fixed and the other being slidable on said standard, a plurality of legs hinged on one of said bracket members and linked to the other to swing into and out of a collapsed position along said standard, yieldable spring latches acting between said legs and standard to hold said legs in a collapsed position, a stem telescopically slidable into one end of said standard, an extension rod telescopically slidable into the other end of said standard and adapted to engage and depress said stem, a compression spring acting between said standard and stem and normally urging said stem inward along said standard, a latch acting between said standard and said extension rod to hold said stem depressed against said compression spring, a shoulder on each of said legs, and cam tracks on said stem shaped and located so as to engage said shoulders and force the legs apart when said extension rod is released by said last-named latch.
3. A screen stand comprising a tubular standard, legs hingedly mounted adjacent one end of said standard and swingable between spread apart positions and collapsed positions against said standard, keeper means on said legs, latch means on said standard shiftable into and out of position for latching engagement with said keeper means, a spring normally urging said latch means out of such latching engagement, a stem connected to said latch means and extending into said standard and an extension rod slidable within said standard and adapted to coact with said stem to shift said latch means into position for such latching engagement against the action of said spring.
4. A screen stand comprising a tubular standard, legs hingedly mounted adjacent one end of said standard and swingable between spread apart positions and collapsed positions against said standard, keeper means on said legs, latch means on said standard shiftable into and out of position for latching engagement with said keeper means, a spring normally urging said latch means out of such latching engagement, cam means connected to and shiftable with said latch means and coacting with said keeper means to spread said legs apart when said latch means are shifted by said spring, and an extension rod slidable within said standard and adapted to shift said latch means into position for such latching engagement against the action of said spring.
5. A screen stand, comprising a standard, a set of legs mounted on said standard to swing between a spread apart position and a retracted position along said standard, shoulders on said legs, a stem slidable along said standard adjacent said legs, leg latch means on said stem and movable therewith into and out of position for latching engagement with such leg shoulders, cam tracks on said stem. adapted to engage such leg shoulders and spread said legs apart as said latch means are moved out of position for said latching engagement, a spring acting between said standard and stem and normally urging said latch means out of said position for said latching engagement, means for retractively energizing said spring and returning said leg latch means to said latching position, and other latch means on said standard adapted to releasably prevent the movement of said leg latch means out of said latching position.
6. A screen stand, comprising a standard, a set of legs mounted on said standard to swing between a spread apart position for supporting said standard and a retracted position along said standard, yielding leg latch means adapted to coact to releasably hold said legs in such retracted position, cam means on said standard and engageable with said legs and movable to force said legs apart, a spring normally urging movement of said cam means to force said legs apart, and other latch means on said standard interconnected with said cam means and adapted to releasably hold said spring and cam means retracted.
LEO J. DU MAIS.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 583,656 McGrady June 1, 1897 1,859,289 Dalton May 24, 1932 2,386,450 Eller Oct. 9, 1945 2,549,584 Eller Apr. 17, 1951 2,591,686 Du Mais et a1 Apr. 8, 1952