US2549584A - Motion-picture projection screen stand - Google Patents

Description

mm W, 1951 E, ELLER 2,5495% MOTION-PICTURE PROJECTION SCREEN STAND Filed Jan. 14, 1947 2 Sheets-Sheet 1 M 1%? H. E. ELLER 9 9 MOTION-PICTURE PROJECTION SCREEN STAND Filed Jan. 14, 1947 2 Sheets-=5heet 2 Patented Apr. 17, 1951 PROJECTION SCREEN MOTION-PICTURE STAND Harry E. Eller, Chicago, Ill.

Application January 14, 1947, Serial No. 721,949

4 Claims. 1

There are in use various types of portable stands on which are mounted screens adapted to be extended, when motion pictures are to be projected thereon, and to be rolled up at other times; the structures as a whole being adapted to be collapsed, when the screens are not in use, to form packages not much longer than the case in which the screen is stored when not in use, and of small transverse dimensions.

The object of the present invention i to produce an improved stand of one of the aforesaid types.

The type of stand to which the present invention particularly relates is that in which there is an extensible post or column supported on legs that may be caused to lie beside and parallel to the lower end of the post, or else be swung outwardly to provide a base in the form of a tripod for supportin the post in an upright position.

Some of the specific objects of my invention are to create a structure in which the legs of the tripod tend constantly to swing outwardly, so that the stand can be quickly set up for use; to provide a simple and novel means for locking the legs in the positions which they occupy when the stand is collapsed and for releasing them when desired; to provide means to cushion the post and to provide against shocks in case the upper extensible section of the post is allowed to drop sharply from a raised position.

Further specific objects of the present invention are to produce a simple and novel latch adapted to lock the two sections of the post against relative lengthwise movement in either direction, while permitting quick and easy release for extending or collapsing the post; to provide simple and novel means to adjust the screen and its casing to compensate for uneven floors and permit the casin to stand horizontal when a floor on which the stand rests slopes a little; and to provide novel means for effectively locking the casing for the screen in a position beside and parallel to the post when the structure as a whole is collapsed.

The various features of novelty whereby the present invention is characterized will hereinafter be pointed out with particularity in the claims, but, for a full understanding of the in vention and of its objects and advantages, reference may be had to the following detailed description taken in connection with the accompanying drawings, wherein: v

Figure l is a front view of a stand embodying the present invention set up for use with the screen partially unrolled; Fig. 2 is a side elevation of the stand in a collapsed state and with the screen housed in its case; Fig. 2A is a View, partly in elevation and partly in section, on a larger scale than Fig. 2, of a small fragment of one end of the screen case and a fragment of the extensible member interlocked therewith; Fig; 3 is a section on an enlarged scale on line 33 of Fig. 1, showing only a fragment of the tripod structure; Fig. 4 is asection on line 4-4 of Fig. 3, showing only the lower end of the post and a fragment of the tripod; Fig. 5 is a view similar to Fig. 4, showing the post pushed down, relatively to the tripod, from the position illustrated in Fig. 4, as is done in locking the tripod in its collapsed condition; Fig. 6 is a vertical section, on a still larger scale, through the upper end of the lower, tubular post member, showing also a fragment of the extension rod that constitute the upper post member; Figs. land 8 are sections taken. respectively, on lines l'-1 and'8--8 of Fig. 6; Fig. 9 is a view, partly in elevation and partly in vertical section, on a larger scale than any of the first eight figures, showing so much of the structure as is needed to illustrate the means for looking the tripod in its collapsed condition; Fig. 10 is a detail, partly in elevation and partly in section, illustrating the means which tends constantly to cause a tripod leg to swing into the ,open or spread position; Fig. 11 is aside view of a fragment of the upper end of the collapsed post and a fragment of a screen casing, showing a modified construction of the parts that cooperate to hold the casing beside and parallel to the post; Fig. 12 is a top plan view of the upper end of the extension rod element of the post in Fig. 11; Fig. 13 is a view similar to Fig. 11, illustrating another modification; and Fig. 14 is a top plan view of the extension rod element of the post in Fig. 13.

Referring to Figs. 1 to 9, 20 is a light tubular member, preferably formed of sheet metal and triangular in cross section. Extending into member 28, through one end of the latter, is an extension rod 2| that is preferably square in cross-section. As shown in Figs. 4 and 5, the lower end of rod 2! rests on a coiled spring 22, when the members 20 and 2| are placed in an upright position with member 2! at the top; the spring resting on a suitable support, such as the transverse pin 23, in the tubular member. The rod may have a plate 24 fastened to its lower end to provide a good bearing on the spring. Members 20 and 2| constitute the post of my improved stand.

The lower end of the post is provided with a collapsible base, preferably legs that may be folded against the same or be swung out to spread over a considerable area. Since three legs, constituting a tripod, is the most desirable construction, I have illustrated and shall confine the detailed description to this particular form of base. The three legs of the base are preferably channeLshaped, the upper end of each pivotally embracing an ear 26 protruding from a sleeve or collar 2? fitting to slide freely on the lower section of the post; rivets 28, or the like, connecting each leg to the corresponding ear. On the extreme lower end of the post is a second sleeve or collar 29, similar to collar 21. C01- lar 29 has a very limited sliding movement, determined by the length of short slots 30 in the post through which passes a transverse pin 31 fixed to the collar. A compression spring 32 is interposed between pins 23 and 3|, so that, when free to do so, this spring pushes collar 29 down so far as the slots permit. Struts or braces 34 extend from collar 29 to legs 25, each being hinged at one end to the collar and at the other end to a leg at about the middle of the latter.

Tension springs 35 are connected at their upper ends to the legs, well above the near ends of the struts; the lower ends of the, springs being attached to the struts a short distance from the adjacent ends of the latter. A convenient way or" fastening the springs to the struts is to hook the free ends thereof through eyes 36 struck up from the web portions of the channelshaped struts. The springs are sufficiently stron to open the tripod by pulling the upper collar or sleeve 2? down; the up and down move- I ment of the collar being limited by the length of the struts and by a pin or stop 31 on the tubular post member below the collar. The latter stop should be placed up far. enough to insure that springs 35 will always be under tension.

There is a hole 38 in tubular post member 20 in position to be covered by collar 21 when the latter is up. The collar is provided with a spring-pressed plunger 39 adapted to enter hole 38 to lock the tripod in its collapsed state. In the arrangement shown, the plunger is slidable in a hollow boss 49 fixed to the collar and containing a compression spring 41 that acts on the plunger. A deep cup-shaped cap 42 fits slidably over boss 4! and is fixed to the outer end of the plunger which protrudes from the boss. When the plunger registers with hole 38, the spring ll forces it into the hole to lock the collar 2'! against movement lengthwise of the post. When the cap is pulled outward, the plunger is retracted and the plunger rides on the outer surface of the post when the collar moves down along the post.

The parts are so proportioned that when 001 lar 29 is at the lower limit of its movement, as in Fig. 4, plunger 39 does not quite register with hole 38, even when the legs are folded against the post, so that the plunger cannot then enter such hole. However, if, after the tripod has been collapsed, the feet thereof are set on the floor and a downward pressure is exerted on the post, spring 32 compresses'allowing the post to slide down a little through the lower collar, as in Figs. 5 and 9, and bring the plunger into registration with the cooperating hole; the plunger snapping into the hole as shown in Fig. 9. The spring 4i draws the plunger against the metal edge bounding hole 38 at the bottom and causes the plunger to be frictionally held in locking position. That looks the tripod securely in its collapsed condition, with its legs lying close to the post.

The extension rod member 2| of the post serves the double purpose of holding the screen case beside and parallel to the post when the stand is collapsed and of supportin the upper end of the screen at any desired elevation above the top of the tubular section 20 of the post When the apparatus is set up for use. In the arrangement shown, the upper end of the rod 2| is bent to form a forwardly directed lateral portion 49. After the stand is collapsed, this portion 49 is pressed down, as shown in full lines in Fig. 2, into engagement with the upper end of the case; conveniently through the provision of a depression 58 in the end of the case, as shown in Fig. 2A, into which the free end of the portion 49 enters.

The rod member of the two-part post is locked, in any position into which it may be moved, by the latch shown in Figs. 6 and 7. This latch consists of a long, narrow hard steel plate 5|, extending crosswise through the upper end of the tubular post member 29, and a strong compression spring 52. One end of the plate is entered loosely in a hole 54 in a flat side of the post to serve as a fulcrum point about which the latch may rock up and down. The other end of the plate extends to the exterior of the post through an opening 55 cut into a corner of the post opposite the flat side containing the hole 54; this opening 55 being of considerable length, measured in the vertical direction, to allow considerable vertical movement of the plate in this region. The protruding angularly bent part 56 of plate 5| constitutes a finger piece. The latch plate contains a hole 5! slightly larger than the cross sectional area of rod 2!, and the rod extends through this hole. The hole in the plate is so made that sharp corners are left beside it on both faces of the plate. Spring 52 rests on plate 5| just inside of the opening 55 and bears at its upper end against a cap 58 secured to the upper end of the tubular post section.

The parts are so proportioned that the latch plate 5| is pressed down far enough by its spring to cause it to grip rod 2| between sharp corners on opposite sides of the rod, before the plate strikes the edge along the lower edge of the opening 55. If it be then attempted to push the rod down, the grip on the rod tightens. Also, although the grip on the rod does not tighten under an upward pull on the rod, the spring causes the latch to maintain its grip until the pull becomes quite strong and accidental displacements which might otherwise occur are prevented.

When the stand is set up and the screen 45 is partially withdrawn from its case 44, the elongated rod hanger 59, which has right-angularly bent ends fixed to the middle of the stick 60 which reenforces the free end of the screen, is slipped over the lateral portion 49 of the extension rod 2| and is placed into a notch 6| in the upper edge of the lateral portion 49. The hanger rod 49 is elongated in the direction of the length of the stick t0, so that is may be shifted transversely to tilt the entire screen unit, including the screen 45 and its case 44 which is pivotally mounted at MB on a tubular portion 46 of the handle 47. By this means compensation may be made for a slope in a, fioor on which the apparatus may have been set up. In Fig. 1, broken line A represents the vertical center line of the screen 45 which normally should be parallel to the axis be made for a post shown in broken lines leaning a little to the left by shifting the center line of the screen a little to the right of the axis of the post. .1

The manner of using my improved apparatus has already been explained to some extent and only a brief further explanation will therefore be needed.

It will be seen that the apparatus is very compact when collapsed, as it is in Fig. 2. The most important new characteristic while in this condition is that the screen case is locked against swinging out of position and the tripod is locked in its collapsed condition. Therefore the apparatus may be carried about by the handle, or otherwise, without fear that some element will become loose and cause annoyance or trouble.

When the collapsed apparatus is to be set up I for use, it is placed in an upright position with the legs resting firmly on the floor in the manner shown in Fig. 2. The locking plunger 39 is then pulled outwardly while the apparatus is lifted off the floor to permit the legs to automatically spread to form a stable base. The leg spread may be varied by simply raisin or lowering the legs about their pivots 28 into the desired angular positions.

The thumb of one hand is then placed against the protruding end 56 of the latch plate 5| and pressure applied thereon to cause upward movement of the latch releases rod 2 I, which may then be moved a short distance out of the end of the tubular member to free the screen case 44 so that the same may be swung crosswise of the post 20 into a horizontal position. The screen is then pulled out of the case 44 and the hanger 59 is slipped onto the laterally extending portion of the rod 2| and dropped into the notch 6| in the latter. While the latch plate 5| is again held in the release position, the extension rod 2| may then be pulled up so far as desired. The screen case 44 may then be moved up by means of handle 4! while its latch 48 is being held depressed in unlocked position to thus adjust the lower end of the screen 45 to desired elevation. The final adjustment may then be made by raisin rod 2| to the desired elevation in the manner heretofore explained.

If the floor is uneven, the screen is leveled by slightly tilting up one side or the other of the screen case and adjustin the hanger 59 accordingly. 3

To take down the screen, the hanger 59 is detached from the upper 'end of the extension member 2| and the screen is allowed to wind up slowly into the case upon the usual spring-actuated roller. Handle 4! is then lowered until it rests on a stop 62 on the post, and the screen case 44 is turned until it is parallel with the post. The extension member 2| may then be released and pushed into the post 20 until the bent end thereof engages within the depression 59 in one end. of the case 44 to lock the case in place. Cap 42 of the locking plunger 39 is then grasped and pulled upwardly until the legs close into collapsed position against the post 29. Then, while holding the legs together and supporting same on the floor, the post may then'be pushed slightly down against the pressure of spring 32 until plunger 39 snaps into hole 38 in the post and locks the legs against spreading.

If during the use of the screen while in extended operative position, for any reason whatever, the rod 2| should be accidentally released and allowed to drop with the weight of the extended screen thereon, spring 22 serves as a cushion to absorb the initial shock and spring 32 serves as an additional cushion to absorb the shock transmitted thereto .by the post and the screen; the post 20 being movable up anddown a little, during use, from the normal position thereof illustrated in'Fig. 4 due to its support on the spring 32. r

' In Figs. 11 and 12 is shown a slightly modified means for locking the screen case 44* when the apparatus is collapsed. Instead of an arcuate extension 49 as shown in Fig. 2, the extension rod member 2| has a straight horizontal extension 49 on the free end of which is a little inverted dish 63 that fits over a pointed end 64* of the cap 64 on the end of the case 44 In Figs. 13 and 14 the extension rod member ZI of the post has no bent upper end, but has applied thereto a cantilever 49 formed from a suitably shaped and folded plate having at one end a socket 49 embracing, and secured as by rivet 49 the rod and at its other end an ovalshaped dish-like part 49 to fit over the pointed end 64 of the cap 64 on the end of case 44*.

While I have illustrated and described with particularity only a single preferred form of my invention, together with a few slight modifications, I do not desire to be limited to the exact details thus illustrated and described, but intend to cover all forms and arrangements that come within the definitions of my invention constituting the appended claims.

I claim:

1. In a collapsible stand, a vertical post, a member mounted on and slidable lengthwise of the post, legs hinged at their upper ends to said member, struts hinged at their lower ends to the post below said member and at their upper ends each connecting a strut and the corresponding leg to cause the stressing of the springs to increase as the slidable member moves upward on said post.

2. A collapsible stand, including a tubular post, a collapsible tripod at the lower end .of said post provided with two axially aligned collars one above the other, a pin extending transversely through said post and the lower one of said collars, a spring cushion supported on said pin within said post, a second pin extendingtransversely of and through the lower end of said post for supporting said post on the upperend of said cushion, said post being slidable within both of said collars and having opposed vertically elongated openings in its lower end through which said first-named pin extends, an extension member slidably mounted within said post, and a second spring cushion supported on said second pin within said post adapted to support said extension member.

3. A projection screen for use on astand having a base and a vertically extensible post comprising a pair of telescoped members rising from the base including a supporting element at the top of the upper one of said post members projecting forwardly therefrom, a projection screen pivotally supported at one end on the lower one of said post members and having at its free end a reenforcing member, and a handle secured to the central portion of said reenforcing member adapted to be engaged with said supporting element to support thereon the free end of the screen in upwardly extended position, said handle having an elongated portion disposed parallel vto said reenforcing member and right-angularly to I the longitudinal center line of the screen and shiftable laterally on said supporting element to facilitate suspension of the screen from said supporting element with the longitudinal center line of the screen disposed in vertical position relatively angularly to the axis of the post when said post rises in a position inclined to a vertical plane due to said base resting on an uneven fioor.

4. A projection screen for use on a stand having a base and a post rising from the base including a supporting element at the upper end of said post projecting forwardly therefrom, a projection screen pivotall supported at one end on an intermediate portion of the post, and a handle secured to the central portion of the free end of the screen, said handle having an elongated portion disposed parallel to the edge of the free end of the screen and right-singularl to the longitudinal center line of the screen.

HARRY E. ELLER.

REFERENCES CITED The following references are of record in the file of this patent:

,UNITED STATES PATENTS 2,386,450 E1161 Oct. 9, 1945

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