US2043981A - Curtain control mechanism - Google Patents

Description

`lune 16, 1936. I T Wi BlCKEL l 2,043,981

CURTAIN CONTROL MECHANI SM Filed Deo. ll, 1934 2 Sheets-Sheet l l N L() Q w v l l o w razz/a5 WOCEeZ INVENTOR ATTOR N EVS June 16, 1936; -4 T. w. BICKEI.

CURTAIN CONTROL MECHANISM 2 sheets-sheet 2' Filed Dec. ll, 1934 ATTORNEYS Patented June 16, 1936 AUNITI-:D STATES PATENT OFFICE CURTAIN CONTROL MECHANISM Travis W. Bickel, Alva, Okla.

Application December 11, 1934, Serial No. 757,016

3 Claims.

The invention relates to mechanism for controlling or Veffecting the opening and closing of curtains such as are used in theaters and has for its general object the provision of a novel power operated device for this purpose and which will at the same time automatically control the house lights, the arrangement being such that as the curtains are moved to open position the house lights will be gradually dimmed, this being particularly advantageous in motion picture theaters though of course not limitedto such.

An important object of the invention is to provide a mechanism of this character in which the entire control is effected by movement of a single switch, thereby reducing the number of necessary parts and greatly increasing the ease of operation.

Another object is to provide a device of this character having m'eans permitting slippage in the transmission so as to avoid danger of damaging'any of the parts after the parts have moved to the predetermined desired limit.

Still another object is to provide a device of this character having a very positive drive so that the operation will be assured.

A more specic object is to provide a novel supporting means upon which the curtains travel, the construction being such as to eliminate any possibility of undesired sag in the curtains themselves.

An additional object is to provide an apparatus of this character which will be simple and inexpensive to make, easy to install and adjust, efficient and durable in service, and a general improvement in the art.

To the attainment of the foregoing and other objects and advantages, the invention preferably consists in the details of construction and the arrangement and combination of parts to be hereinafter more fully described and claimed,

' and illustrated in the accompanying drawings in which:

Figure 1 is a perspective view of the complete device,

Figure 2 is a detail section taken along the main drive shaft,

f Figure 3 is a similar view through the transmission for controlling the lights,

Figure 4 is a diagram of vthe electrical circuits, and

Figure 5 is a detail view of the light dimming resistance device.

Referring more particularly to the drawings the numerals IIJ and Il designate a pair of curtains of any ordinary or preferredY construction and ofthe type used in front of the stage or screen in a theater. These curtains are shown as suspended by means of suitable loops I2 from a pair of horizontally disposed parallel bars or rods I3 and I4 which are mounted in brackets I5 and I6. Of course the curtain I slides on the rod I3 in overlapping relation to the curtain II which slides on the rod I4. The brackets I limit the separating movement of the curtains while the brackets I 6 act as stops for maintaining them in overlapping relation when closed.

At one side of the pair of curtains there is provided a pulley I1 mounted in a bracket I8, and at the other side are two pulleys I9 and 20 mounted in a similar bracket 2|. For moving the curtains there is provided a rope or cable 22 which is trained over the pulleys I9 and 2i) and about the pulley I'I. Opening and closing of the curtains is effected by pulling upon this rope in one direction or the other by means of the mechanism to be described.

The power device for operating the curtains is represented as comprisingra support 23 which may be a casting and which includes bearing portions 24 and 25 and a housing 26. Journaled through the bearing portions is a shaft 21 upon which is mounted a Worm' wheel 28 located Within the confines of the casing or housing 2G and meshing with a worm 29 on the shaft 30 of an electric motor 3| which is mounted in any convenient manner upon the support 23. Fixed upon the shaft 2l for rotation therewith is a small sprocket 32, and loose upon the shaft is a larger sprocket 33 which is intended at times to rotate with the shaft and at other times to slip with respect thereto, as will be explained. 'I'his drive mechanism further includes a specially constructed clutch comprising a collar 34 splined at 35 onto the shaft 2l and carrying a friction member 36 bearing against a similar friction member 3l mounted on a ring 38 secured to the sprocket 33. Acoil spring 39 surrounds the shaft 21 an-d bears against the collar 34 for the purpose of urging it toward the sprocket. The other end of the spring abuts against a collar 4U which rotates with the shaft 21 but which is also slidable thereon. The particular connection is represented as consisting of a pin 4I which passes through the hub of the collar and through a transverse slot 42 in the shaft 21. From this slot to the adjacent end the shaft is formed with a bore 43 into which extends a screw 44 which is threaded into the outer end o-f the shaft and which is equipped with a head 45 by means of which it may be turned for the purpose of adjusting the tension of the spring 39 and consequently the degree of frictional engagement between the friction faces 36 and 3l, it being clear that by rotating the operating head 45 in a clockwise direction the engagement of the end of the screw 44 with the pin 4I will move. the collar 4B toward the sprocket 33 and increase the pressure exerted by the spring. Rotation of the head 45 inthe opposite direction will of course reduce the frictional engagement so that the clutch can slip more readily.

Trained about the sprocket 33 is a chain 46 which has its ends connected with the ends of the above mentioned rope or cable 22, stop balls 41 being provided at the junctures. By this construction it will be seen that when the motor 3l is operated and the sprocket 33 rotated the curtains I0 and Il will be moved together or apart depending upon the direction in which the motor is operating. For controlling the motor there is provided a control box 48 containing a double throw switch 49 of any ordinary or preferred type and connected with the field 50 and armature 5| of the motor in such manner that when the switch is at one limit of its movement the motor will run in one direction whereas the motor will be reversed when the switch is moved in the other direction. The connections are shown in the diagram, Figure 4, and as such switches are old and well known it is not beiieved that elaborate description is needed. The 'control box is also represented as containing a pair of pilot lights 52 and 53 which may be of contrasting colors so as to indicate the direction of rotation of the niotor and also to indicate whether or not the motor is in neutral or cut oif position, both of the pilot lights being out at such a time.

A very important feature of the invention resides in the provision of means for automatically dimming and brightening the house lights in accordance with movement of the curtains. To accomplish this I provide a suitable support 54 in which is journaled a shaft 55 carrying an arm 56 which is connected with a contact arm 5l movable over a. series of contacts 58 tapped oft at spaced points in the length of a resistance coil 53 mounted in an appropriate casing 63 likewise mounted on the support 5t.

Rotatable on the shaft 55 is a sprocket t! about which is trained a chain G2 in turn trained about the small sprocket 32 on the shaft 2'! of the main drive. The same type of slippage permitting clutch is provided in association with the sprocket 6l and is represented as inclu-ding a friction member G3 on the sprocket coacting with a similar friction member or face 54 on a collar 65 keyed to the shaft 55. The sprocket is slidable on the shaft and is urged toward the collar 65 by a spring 56 which abuts against a collar S7 slidable on the shaft and engaged by an adjusting screw 68 which is threaded into the hollow end of the shaft as cleariy shown in Figure 3. By turning the screw S8 in or out the pressure exerted by the spring 6G against the sprocket can be controlled so as to permit the clutch to slip upon the occurrence of a certain predetermined degree of torsion.

In the operation, it will be seen that assuming that the curtains are closed as shown in Figure 1 and it is desired to open them the operator must throw the switch 49 whereupon the motor will start and by virtue of the friction clutch consisting of the parts 33 to 42 the sprocket 33 will be driven, thereby moving the chain 4S and pulling upon the rope 22 which, having its ends connected with the curtains, will result in drawing them along the rods or rails I3 and i4 into open position. As soon as this is effected the clutch will slip so that no damage will result to the parts. At the same time that this occurs, the rotation of the sprocket 32 driving the chain 62 will cause the sprocket 6I to be rotated whereupon by virtue of the friction clutch connection consisting of the parts 6l to 68 the shaft 55 will be rotated, the arm 56 moving the contact arm 51 over the series of contacts 58 and thereby cutting more and more resistance into the circuit of the house lights so that the lights will be gradually dimmed as the curtains are opened. When it is desired to close the curtains the reverse action is performed as the result of throwing the switch in the other direction.

From the foregoing description and a study of the drawings it will be apparent that I have thus provided a very simply constructed mechanism which may be operated from any desired point depending upon where the control switch is located. This device is bound to be of great advantage in that the curtains are adequately supported and therefore cannot sag. Moreover the feature of the automatic dimming and brightening of the house lights in accordance with the curtain positions is a distinct advantage particularly in motion picture theaters, It is believed from the foregoing that the construction, operation and advantages will be readily apparent to one skilled in the art without further explanation.

While I have shown and described the preferred embodiment of the invention, it should be understood that the disclosure is merely an exemplification of the principles involved as the right is reserved to make all such changes in the details of construction as will widen the field of utility and increase the adaptability of the device provided such changes constitute no departure from the spirit of the invention or the scope of the claims hereunto appended.

Having thus described the invention, I claim:

l. A mechanism for opening and closing theater curtains, comprising means for slidably supporting the curtains to overlap in closed position, a shaft, a motor operated transmission for driving the shaft, friction means permitting slippage in the transmission, means driven by the shaft and connected with the curtains for sliding them in opposite directions to open position and to overlapped closed position, and means for adjusting the friction means.

2. A mechanism for opening and closing slidably suspended theater curtains, comprising means for supporting the curtains to overlap in closed position, a motor, a transmission mechanism driven by the motor and including a shaft, a sprocket rotatable on the shaft, a friction clutch for locking the sprocket to the shaft, means for adjusting the friction of the clutch, a chain trained about the sprocket, and a iiexible member connected with the ends of the chain and operatively connected with the curtain supporting means to slide the curtains oppositely to each other to open position and to overlapped closed position.

3. A mechanism for opening and. closing slidably suspended theater curtains, comprising means for supporting the curtains to overlap in closed position, a motor, a shaft driven by the motor, a sprocket rotatable on the shaft, a friction clutch for locking the sprocket to the shaft, means for adjusting the friction of the clutch, a chain trained over the sprocket, a flexible member connected with the ends of the chain, guides for the iiexible member, and means connecting the flexible member with the curtains for moving them in opposite directions to open position and to overlapped closed position.

TRAVIS W. BICKEL.

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