US1874077A - Counterbalancing device - Google Patents

Description

E. G. ANDERSON COUNTERBALANCING DEV-ICE Filed Dec. 24, 1929 Aug, 3%, 132.

Ti -l.

ATTORNEYS.

Patented Aug. 30, 1932 UNITED STATES,

ELLIs G. ANDERSON, OF OKLAHOMA CITY, OKLAHOMA cOUfirEnBALANcmG DEVICE Application filed December 24, 1929.

This invention relates to a counterbalancing device which is designed and adapted to operate in conjunction with curtains or doors which are wound on and unwound from an Ll! overhead winding core, roller orbarrel, and

also to operate in conjunction with any appurtenances whose weight varies in operation under the influence of a directgravity ull. P The principal object of the invention is the provision of a device of the indicated character having means for making the desired adjustments, to compensate for any variations in the widths of curtains, doors and the like, and corresponding variations in weights of curtains, doors and the like of the same size, but made of materials of various weights.

With the foregoing, other objects of the invention will appear from the embodiment of the invention which by way of example is described in the following specification and illustrated in the accompanying drawing, in which I Figure 1 shows the device of the present invention applied by way of example to a roller door, the same being rolled up, and a portion thereof being broken away;

Figure 2 is a section on the line 22 of Figure 1 looking in the direction indicated by the arrow;

Figure 3 is an end view of the pulley;

Figure 4 is a fragmentary face view of the grooved part of the pulley.

As stated, the device of the present invention is one which may be employed in conjunction with a curtain or door which is wound on and unwound from a suitable winding core, roller or barrel. In Figure 1 of the drawing there is shown an axle or shaft mounted for rotation in suitable bear-.

Serial No. 416,283.

tion of gravity. It will be understood that the weight imposed on the axle 10 as the door is wound and unwound will vary.

. In other words, the weight or force imposed on the axle 10 increases as the door is u unwound, and decreases as the door is wound on the barrel 12.

The device of the present invention includes a pulley 14 consisting of a part 15 and a part 16. The part 15 is of conical form, and has a helical groove 17, the convolutions of which increase progressively from the small end to the large end of the part 15. The part 15 is loosely mounted on one end of the axle 10. I

The part 16 of the pulley is in the form of a disk having a hub 18 which carries a set screw 19. The part 16 is adapted to be mounted on the axle end adjacent the part 15 and is securely held in place thereon by I0 the set screw 19. Use is made of a weight 20 of suitable size and a flexible element 21 such as a cord which has one end thereof connected with the weight 20 and the opposite end thereof is detachably connected by 76 a headed element 22 with the part 15 of the pulley. The part 15 has a plurality of holes 28 any one of which is adapted to'accommodate the element 22 to change the connection of the flexible element 21 with the part 15, for the purpose of making the desired adjustment to compensate for variations in the weight of the door, to a limited extent.

In order to further adjust the parts of the pulley to compensate for variations in the weight so that the proper counterbalancing efl'ect may be obtained, the part 16 is provided with a series of holes 24 arranged concentrically with respect to the axis of the part 16, and the part 15 of the pulley has a plurality of threaded holes 25. Use is made of set screws 26 equal in number to the number of'holes 25. The set screws 26 are receivable respectively in certain of the holes 95 24 of the part 16 andare threaded in holes 25 of the part 15 to securely hold the parts 15 and 16 of the pulley in the desired adjusted relationship. In this manner the necessary and desired adjustment of the pulley 14 may be made to com ensate for variations for the reasons state herein above.

From the foregom 1t W111 be apparent that when the door 13 1s wound upon the bar.-

rel 12, the flexible element 21 will be unwound from the part 15 of the pulley with the counterbalancin g weight 20 in the down posltion. When the door 13 is unwound from the barrel 12, the flexible element 21 will wind .on the part 15 of the pulley, thereby raismg the counterbalancing weight 20, which serves to counterbalance the increasing weight of the door as it is being unwound from the barrel 12. 1

I claim:

1. A counterbalancing device of the class described including a rotatable axle, a pulley adapted for winding thereon and unwinding 1 therefrom a counter-weight flexible sustaining element, said pulley comprising a part for said element loosely. mounted on said axle, a part fixed on said axle, and means adapted to secure said parts together in any;

desired adjusted relation with respect to cite other.

2. A counterbalancijng device of the class 7 described including a rotatable axle, a pulley adapted for winding thereon and unwindingtherefrom a counter-weight flexible sustaining element, said pulley comprising a part'for said element loosely mounted on said axle, a part fixed on -said axle, and

securing means on said parts to connectsaid w parts togetherin any desired adjusted relation with respect to each other.

3. A counterbalancing device of the class described including a rotatable axle, a pulley adapted for winding thereon and unwinding therefrom a counter-weight flexi ble sustaining element, said pulley comprising a part for said element loosely mounted on said axle, a part fixed on said axle, each of said parts having apertures therein, the apertures in one'part being arranged to be brought into registry with the apertures in the other part, and the sides of theapertures;

in the latter part each being threaded, and

fastening elements receivable respectively in the apertures in one part and capableof be ing threaded in the registeringapertures' in the other part for the purpose specified.

ELLI G. ANDERSON,

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