US2638184A - Rope locking pulley assembly - Google Patents

Description

y 12, 1953 R. STURDIVANT 2,638,184

ROPE LOCKING PUL'LEY ASSEMBLY Filed Nov. 8.. 1948 uvmvron Patented May 12, 1953 UNITED STATES PATENT oFFiclE 2,638,184 1 p p ROPE LOCKIN G PULLEY ASSEMBLY 9 Robert Sturdivant, Nashville, Tenn.

Application November 8, 1948, Serial No. 58,919

2 Claims.

The present invention relates to a new and improved pulley assembly provided with means for locking the rope or cord against running in one direction through the pulley.

Among the objects of the invention are to provide a simple and inexpensive pulley assembly which eifectively locks the rope against running in one direction through the pulley, which does not unduly wear or fray the rope and which functions to more securely lock the rope as the tension therein increases in the direction tending to cause the rope to run through the pulley in the undesired direction.

Additional objects and advantages of the invention will be referred to in the following detailed description which has reference to the accompanying drawings wherein:

Figure 1 is a side elevation View of a pulley assembly embodying the novel features of the present invention;

Figure 2 is an elevation View showing one edge of the pulley assembly;

Figure 3 is a perspective view of the rope locking or clamping member; and

Figure 4 is an enlarged fragmentary view of the rope engaging portion of the locking member.

The assembly includes a grooved sheave 5 which is rotatably mounted on an axle 6. The

frame includes side plates 1 and 8 disposed on opposite sides of the pulley 5 and through which the ends of the axle 6 project. The side plates 1 and 8 are joined at their upper ends by a semispherical crown 9 which is preferably integral with the side plates. The crown 9 is provided with an eye It which is secured thereto by any suitable means and which is used for suspending the assembly.

Rivets II and I2 extend through and between the side plates 1 and 8. These rivets are spaced slightly below the lower surface of the crown 9 and they cooperate with that lower surface to provide a horizontally extending guideway through which a locking member I3 is slidable.

The locking member I3 is shown in the form of a strip of rigid metal and includes a central portion M, an angularly disposed rope engaging portion l5 at one end and an angularly disposed tab It at the opposite end which facilitates manipulation of the locking member. The rope engaging portion |5 extends at an acute angle from the central portion l4 toward a position on the periphery of the sheave 5 which is below the crest or highest elevation of the sheave. The free end of the portion [5 is concave as indi- (Cl. l88--64) cated at H to conform to the rope it which passes through the assembly. The term rope is here used in its broader sense and is intended to include ropes and cords of whatever nature or size. The rope engaging face I! is provided with a plurality of projections or teeth l9 to effectively engage the rope without slipping.

Figures 1 and 2 illustrate the locking member l3 in position to prevent the rope 18 from running through the pulley in the direction indicated by the arrow 20. The concave face I! of the rope engaging portion i5 is in engagement with the rope I8 and the rope is clamped between that concave face and the groove in the sheave 5. It will be apparent from an inspection of Figure 1 that tension on the rope l8 tending to cause it to run in the direction of the arrow 20 will cause the rope engaging portion [5 to more tightly engage and clamp the rope. The rope l8 may be released to run freely through the pulley assembly merely by pushing the tab 16 to the left as the assembly is viewed in Figure 1. When the rope reaches the desired new position it can be again locked in place by pushing to the right on the tab l6.

Conventional pulleys may be modified to embody my invention by providing some suitable means for forming the guideway for the locking member [3 and inserting the locking member in the guideway thus provided. Careful machining and proportioning of the various elements of the assembly is not required and the assembly thus lends itself to quantity production at low cost. The locking of the rope is essentially a clamping or squeezing action and I have found that it does not cause undue wear or fraying of the rope.

I have illustrated and described what I now consider to be the preferred embodiment of my invention. However, it will be apparent that various alterations and modifications may be resorted to without departing from the broader scope of the invention as defined by the following claims.

Having thus described my invention, I claim:

1. A rope locking pulley assembly comprising a sheave, an axle for said sheave, an elongated plate on each side of said sheave for supporting the ends of said axle, said plates being joined together at a corresponding end of each plate and being provided with means for suspending the assembly, means connected to at least one of and lying between said plates, and between the joined ends thereof and the periphery of said sheave, for providing a guideway, a bar-dike locking member having a generally rectilinear central portion slidable in said guideway, said locking member comprising a strip of sheet-metal bent near its rope-engaging end to form an angularly disposed portion extending from one end thereof toward the periphery of said sheave with the free end of said portion being arranged to engage and clamp a rope against said sheave to prevent running of the rope in one direction relative to the assembly, the point of engagement of said angular'ly disposed portion lying between 25 and 65 degrees of are measured around said sheave from a point thereof closest to the generally rectilinear central portion of said locking member" 2. A rope locking pulley assembly according to claim 1 and additionally comprising a second angularly bent portion at its other end to provide a stop means to prevent inadvertent separation of said locking member from said pulley assembly.

ROBERT STU'RDIVANT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 527,425 Hartz in--. Oct. 16, 1894 538,584 Hartz Apr, 30, 1895 1,122,126 Jurgens Dec. 22, 1914 2,532,893 Crotty Dec. 5, 1950 FOREIGN PATENTS Number Country Date 723,992 France "in Apr. 18, 1932

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