US2495459A

US2495459A - Demountable sheave

Info

Publication number: US2495459A
Application number: US34070A
Authority: US
Inventors: Kessler David Lowell
Original assignee: Gates Rubber Co
Current assignee: Gates Rubber Co
Priority date: 1948-06-19
Filing date: 1948-06-19
Publication date: 1950-01-24
Anticipated expiration: 1967-01-24

Description

Jan. 24, 1950 D. 1.. KEssLER 2,495,459

DEMOUNTABLE SHEAVE Filed June 19, 1948 mmvrox. DAV/D lam 6H A ess/cr Patented Jan. 24, 1950 DEMOUNTABLE SHEAVE David Lowell Kessler, Denver, 0010., assignor to {Gates Rubber Company, Denver, 0010., a corpo- V ration of Colorado Application June 19, 1948, Serial No. 34,070

3Claims. '(Cl. 74-230.01)

This invention relates to improvements in sheaves, more particularlyto sheaves of the multiple groove type employed in connection with multiple V-belt power transmissions, but'is not limited to such use.

It is the object of this invention to produce a sheave assembly of a two-part construction, comprising a hub andarim assembly of such construction that 'the same rim may be com bined with hubs-bored for the reception'of shafts of different sizes and in which rims of difierent diameters may be combined with'thesame'hub.

Another object is to produce a sheave of such construction that the hub can be clamped to' the shaft by means of the: rim so that torquegfrom the shaft can be transmitted through thesheave without'the necessity ofsplines or keys between the shaft and the hub.

Another object is toproduce a=sheave assembly of such construction that it can be easily and quickly attached to and removed from a shaft.

A further object is to provide a sheave assembly of such, construction that the rim portion may be positioned on the hub in two longitudinally different positions.

A still further object is to provide a sheave assembly of such construction thatthe rim may be removed from the hub while the latter is in position on the shaft so that rims of different sizes may be quickly substituted.

The above and other objects that may appear as the description proceeds are attained by means of a construction and an arrangement of parts that will now be described in detail, and for this purpose reference will be had tothe accompanying drawing in which the invention has been illustrated, and in which:

Figure l is a diametrical section through a sheave assembly, taken on line Il, Figure 2;

Figure 2 is a side elevation of the sheave looking towards theleft in Figure 1;

Figure 3 is a sectiontaken on 1ine.33, Figure 4;

Figure 4 is a side elevation looking towards the left in Figure 3; and

Figure 5 is a partial section similar to that shown in Figure 1 and showshow a run like shown in Figure 3 can be employed with the hub to effect additional longitudinal adjustment.

Referring now to the drawing, reference numeral l5 designates the hub which has an axial opening of any desired size and which is provided with an outwardly extending flange It. Inclined or outwardly tapered surfaces I! and I1 extend from opposite sides of the flange as shown in Figure 1. Thehub and the flange are separated by means of a diametrical saw cut i8 which extends from a point approximately at the inner diameter of flange 16 on *oneside to the outside and entirely through the flange on the a tapered opening of somewhat smaller diameter than the normal diameter of inclined surfaces l7 and H so that when web 22 is in the position shown in Figure 1 and forced againstflangelB by means of the cap screws 20, thehub will be;

contracted slightly so as to force the inner -surface of the opening therein into frictional engagement with a shaft. Of course it is understood that the opening in the'hub must be of such a diameter that the hub can:be-s1id onto the shaft with an easy sliding fit and after it has been properly positioned on the shaft, the hub and rim assembly can then be clamped frictionally to the shaft by tightening the cap screws so as to bring the opposing surfaces of the flange and web into engagement.

Referring now to Figures 1 and 2, it will be observed that flange 16 is nearer one end of the hub than the other. In this specific embodiment, the inclined surface 11 isof thesamewidth as the thickness of web 22 so that when the parts are in assembled and operative position, the end of the hub will be in the same plane as the outer surface of web .22. 7 When the two parts are assembled as shown in Figure 1, the sheave will project a short distance beyond the-outer end of the hub. However, if the rim is reversed so as to bring it onto the inclined surface H, the two parts will still retain substantially the same longitudinal relation as shown in Figure 1. It is to be understood that rim 2| may have either a greater or a lesser nurnber of groovesthan those shown and it therefore becomes a great -corrvenience to be able to reverse the parts in the manner made possible due to thedoubleinclined or conical surfaces [1 and J1.

In Figures 3 and 4 a slightly modified form of construction has been shown. The hub has been designated by reference numeral I5a and is provided with an outwardly extending flange 16a. A frustoconical or inclined surface l'la extends outwardly from the outer surface of flange Ilia. Rim Zla has been shown as having five grooves instead of four as in Figures 1 and 2 and web 22a is somewhat thicker than web 22 and has the wall of its opening provided with two outwardly flaring tapered surfaces 23. Web 22a is provided with six holes. Those designated by reference numeral 24 are for the reception of cap screws 25. threaded, but have no corresponding holes in flange [6a. When the sheave assembly shown in Figures 3 and 4 is applied, the rim is positioned either as shown in Figure 3, or it may be reversed; in the latter case it will extend inwardly beyond the inner surface of the hub. Such arrangements are sometimes necessary in connection with certain machinery. After the hub has been positioned on the shaft, screws 25 are tightened, forcing web 22a upwardly along the inclined surface Ila, thereby contracting the hub about the shaft forcing the same into frictional engagement with the shaft. Due to the small taper and to the fact that the cap screws, when properly tightened, will exert a strong force, the hub is contracted above the shaft with suflicient force to form a frictional engagement that will prevent accidental rotation in the absence of keys or splines.

It will be observed that in both forms of the invention shown, flanges i6 and ifia and

webs

22 and 22a are positioned to one side of the middle point of each part. This makes it possible to obtain various longitudinal adjustments that are very useful in effecting the proper positioning of the sheaves to bring them into alignment with cooperating sheaves on spaced parallel axes. When the rim is to be removed, for example, if it is to be replaced by one of a greater diameter, the securing bolts are removed and two of them are positioned in the threaded holes 28 and moved inwardly towards the surface of flange I6a, thereby producing a force tending to move the web outwardly and effect a release between the two parts.

It is pointed out that the rim shown in Figures 3 and can be used with the hub illustrated in Figure 1, whereby a variety of adjustments may be effected. In the same manner the rim shown in Figure 1 can be used with the hub shown in Figures 8 and 5. Figure 5 shows how a rim having a flange 22a with oppositely inclined frustoconical surfaces can be substituted for the one shown in Figure 1 so as to effect additional adiustments in the manner explained in connection with Figures 3 and 4.

With the hub illustrated in Figure 3, two adjustments may be made, one of said adjustments is the one illustrated and the other involves turning the rim in the opposite direction.

With the hub shown in Figure 5 and the rim shown in Figures 3 and 5 for different adjustments may be made, two on each side of the flange.

Having described the invention what is claimed as new is:

1. In a demountable sheave of the power transmission type, comprising a hub having an axial opening for the reception of a shaft, a flange surrounding the hub in a plane perpendicular to its axis, there being an outwardly tapering The holes designated by numerals 26 are.

frusto-conical surface on each side of the flange, the flange being positioned nearer one end of the hub than the other, the hub and flange having a radial saw kerf, a rim having an inwardly extending flange provided with a central opening, the wall of said opening having two outwardly flaring surfaces of the same taper as the tapers of the frusto-conioal surface on the hub, the diameters of the openings in the flange of the rim being slightly smaller than the corresponding outside diameter of the hub, whereby the opening in the hub will be reduced when the I rim is in position and forced towards the flange on the hub, the flange being nearer one end of the rim than the other, whereby the hub and flange may be assembled in any one of four different relative longitudinal positions.

2. In a demountable sheave of the power transmission type, comprising a hub having an axial opening for the reception of a shaft, a flange surrounding the hub in a plane perpendicular to the hub axis, the hub having an outwardly tapering irusto-conical surface on one side of the flange, the hub and flange having a radial saw kerf, a rim having an inwardly extending flange provided with a central opening, the opening wall comprising two outwardly flaring frustoconical surfaces of the same taper as the frustoconical surfaces on the hub, but of slightly smaller radii, whereby when the rim is positioned on the hub with one of its tapered surfaces in engagement with the outwardly tapered surface of the hub and forced inwardly towards the flange, the opening in the hub will decrease in diameter, the inwardly extending flange on the rim being spaced nearer one end than the other, whereby the hub and rim may be assembled in two different relative longitudinal positions by reversing the rim relative to the hub,

3. In a demountable sheave of the power transmission type, comprising a hub member having an axial opening for the reception of a shaft, a rim having an inwardly extending flange member adapted to axially telescope over the hub member, one of said members having a pair of frusto-conical surfaces extending in opposite directions from a plane therebetween normal to the hub axis, the surfaces intersecting at said plane, at least one frusto-conical surface on the other member engageable with one of said pair of frusto-conical surfaces, a flange surrounding the hub, the last named flange and the hub having a slot therein to permit contraction of the hub on a shaft, and means for drawing said inwardly extending flange member toward the last named flange to secure the rim to the hub and contract the hub on a shaft.

DAVID LOWELL KESSLER.

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

UNITED STATES PATENTS Number Name Date 1,580,919 Reeves Apr. 13, 1926 2,269,821 Kemphert et a1. Jan. 13, 1942