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place where the wages are the highest is the place where the goods are made the cheapest, then you have field enough before you for the rest of your lives.

Mr. SMITH. I witnessed the operations of the Dederick cotton-press, while I was down at Atlanta; and I should like to offer this resolution,

Resolved, That the attention of the Committee be called to the merits of the Dederick press, and that they report to this Association the results of their investigation.

The resolution was adopted.
The meeting then adjourned.

METHODS

OF TRANSMITTING POWER BY BELTS WHEN THE AXES OF THE CONNECTING SHAFTS

ARE NOT PARALLEL.

BY NATHANIEL HILL, Esq., LOWELL, Mass.

ILLUSTRATED.

(COPYRIGHT SECURED.)

You have, sometimes, occasion to connect shafts which are not parallel, by means of a belt. When there is considerable difference of height, and little power to be transmitted, you make use of a belt without guides, with the pulley's so placed that the belt will keep on the pulleys when running in one direction, as in this model (Fig. 4), where the belt remains on the pulleys at whatever angle I turn this upper pulley ; the belt drawing on to each pulley from a point in the plane of that pulley.

But there is always a side or tearing strain on both the tight and slack sides of the belt, at the points where it leaves the pulleys (A, A', Fig. 4); and, if the motion is reversed, the belt at once “ runs off," as it no longer draws from a point in the plane of the pulley. When a heavy power is to be transmitted, this tearing strain is olijectionable ; and you then resort to the device of arranging the pulley's so that the belt shall draw with an even strain on both edges, from the driven-pulley to the driver on the tight side, leading the belt back to the driven-pulley by means of guide-pulleys more or less perfectly arranged. Here (Fig. 10) is a model of an arrangement that has been in use many years, I have been told, at the arsenal at Springfield and at other places. A pulley on each shaft, F, F', may be taken for the working-pulleys, the two others being guides. or course, it would not be advisable to have the guides, turning, as they do, in a reverse direction, run on the shafts of the working-pulley's ; but they may be placed in the line of their present places, either beyond, or between the shafts. This arrangement is somewhat cumber

some, and inconvenient to apply. The belt, however, runs perfectly in either direction, and for this reason, that the two portions of belt, one on either side of each of the four pulleys, lie in the plane of that pulley: the belt therefore draws, with reference to each pulley, from a point in the plane of that pulley when moving in either direction. The same result may be attained in other arrangements. This model (Fig. 2) has the guides in the same plane, the face of one, in a vertical line with, and below the face of one working-pulley; the face of the other, in a vertical line with, and over the face of the other working-pulley: the belt drawing direct from one working-pulley to the other, on the tight side. This arrangement permits the guides to be placed on horizontal shafts, as in the last model (Fig. 10), and, without placing the guides beyond the shafts of working-pulleys, can always be used when there is distance between the working-pulley's to make the required quarter-twist in the belt; as there is always room to make the slight twist between working-pulleys and guides. The guides may be placed at any convenient height, the belt being looped over one and under the other guide, or merely deflected by each guide. The guides may also be used as tighteners by vertical adjustment, as may those of the model last shown.

We can also guide the belt in the same perfect manner by means of a single pulley (Fig. 1), or by two pulleys in the same plane (Fig. 3), so placed as to carry the slack portion of belt near each workingpulley, back in the plane of that pulley, toward the tight side of the belt. When the two pulleys are used, they may be used as tighteners by moving them parallel to that portion of the belt extending from the guide to the adjoining working-pulley. Or, we may use two guides in a manner to bring the straight portion of belt between the guides, near to, and almost parallel to, the tight side of the belt (Fig. 5). There being nearly a quarter-twist between the guides, this arrangement is applicable only where there is considerable distance between the working-pulleys; as when the belt passes through a story between those in which the shafts run. The position of the guides in all these cases, and generally in all cases that present any difficulty, may be determined by tracing by means of a cord, a path for the belt, so that the portion of cord on either side of each working-pulley lies in the plane of that pulley, then placing the guide in the plane of, and touching adjoining portions of the cord where it is deflected from the plane of one pulley to that of the other.

When it is desired to know the position of the guides before the working-pulleys are in position, every point can be determined by means of a drawing, which is of necessity somewhat complex; or, if the importance of the case demands, the position may be exactly calculated. The cases last shown will be referred to again.

When the shafts to be connected are at nearly the same height, we must always use a guide on the tight side of the belt. This arrangement (Fig. 11, which is the same model as Fig. 10, opened out) shows the ordinary overhead quarter-turn belt, arranged for working-pulleys of same size, and at the same height. In this case the guides may be placed on a vertical shaft, and the belt will run in either direction perfectly. The guides cannot, however, be used as tighteners, and the position is not a desirable one in which to run a very heavy belt. For all other cases than that of equal speed and equal height, of shafts, the position of the guides, to admit of perfect running, must be determined by means of the cord, or by drawings, as explained.

The arrangement now shown (Fig. 12) is copied from a sketch furnished me, of a belt now running, in which the two guides are on horizontal shafts, and are at about the same height; it will admit of a change of speed between the two working-shafts, which may also differ in height. The belt will run only in one direction, and has the defect of a side strain on both the tight and slack sides ; while here (Fig. 13) is a model similar in arrangement, in which the belt will run in either direction, and, of course, without the side strain in the belt.

Nearly two years ago I was called upon to arrange a belt, to connect shafts at nearly the same height, in the mills of the Appleton Company at Lowell. The agent preferred to use a looped belt rather than an open belt to a shaft in another story, and from there return with a quarter-turn belt with guides, as he could thus accomplish the result by the use of four pulleys and one belt, while the other arrangement involved the use of six pulleys and two belts. I proposed the arrangement here shown (Fig. 6), which has guides on horizontal shafts. A portion of the power may be taken off on one of the guides, thus delivering power to two stories at right angles to the driving-shaft; and the other guide may be used as a tightener. It was found that a floor-beam (T, Fig. 15), shown here in a model made to scale, interfered with the passage of the belt from one pulley to the guide: to avoid this, I proposed to use a smaller guide (N, Fig. 15), and so set, that the belt should run correctly in either direction. Fig. 9 is the same arrangement, but of different proportions, to show more plainly the canted guide. I determined the position of the guide by calculation ; and, when a trial belt was put on, it was found to run perfectly in either direction. It was designed to transmit 120 horse-power with an eleven-inch double belt, running about 5,200 feet per minute. It is believed that it was used to transmit 150 horse-power, always giving satisfaction, and is now to be replaced by an arrangement to transmit a much greater amount of power.

some, and inconvenient to apply. The belt, however, rups perfectly in either direction, and for this reason, that the two portions of belt, one on either side of each of the four pulleys, lie in the plane of that pulley : the belt therefore draws, with reference to each pulley, from a point in the plane of that pulley when moving in either direction. The same result may be attained in other arrangements. This model (Fig. 2) has the guides in the same plane, the face of one, in a vertical line with, and below the face of one working-pulley; the face of the other, in a vertical line with, and over the face of the other working-pulley : the belt drawing direct from one working-pulley to the other, on the tight side. This arrangement permits the guides to be placed on horizontal shafts, as in the last model (Fig. 10), and, without placing the guides beyond the shafts of working-pulleys, can always be used when there is distance between the working-pulley to make the required quarter-twist in the belt; as there is always roo to make the slight twist between working-pulleys and guides. T guides may be placed at any convenient height, the belt being loop over one and under the other guide, or merely deflected by po guide. The guides may also be used as tighteners by vertical adi ment, as may those of the model last shown.

We can also guide the belt in the same perfect manner hy 11:' of a single pulley (Fig. 1), or by two pulleys in the same plane i 3), so placed as to carry the slack portion of belt near each worl pulley, back in the plane of that pulley, toward the tight side of belt. When the two pulleys are used, they may be used as tighte by moving them parallel to that portion of the belt extending from guide to the adjoining working-pulley. Or, we may use two gr in a manner to bring the straight portion of belt between the go near to, and almost parallel to, the tight side of the belt (Fig There being nearly a quarter-twist between the guides, this ar ment is applicable only where there is considerable distance bel the working-pulleys; as when the belt passes through a story be those in which the shafts ren. The position of the guides these cases, and generally in cases that present any difficult be determined by Lacing by mears of a cord, a path for the that the portion of cand on either side of each working-pl in the plane of that pules, the placing the guide in the play and touching vidjoining portions on the cord where it is from the plane of one sulley to that over

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