GUIDE PULLEYS 



81 



through the center of the face of each pulley should coincide 

 with the planes formed by these tangents. The illustrations 

 Figs 24 to 27 show various arrangements of guide pulleys. 

 Others will suggest themselves according to the needs of each 

 particular case. It is only necessary to observe the precau- 

 tion that the guide pulleys be so placed that they will receive 

 the belt squarely from the main pulley and deliver it squarely 

 to the next one. If this be done, the pulleys may be placed 

 in practically any location and at practically any angle. 



FIG. 25. SINGLE GUIDE PULLEY. 



A common arrangement of guide pulleys, known as a 

 mule pulley stand, is shown in Figs. 28 and 29. The method 

 followed in locating the pulleys and determining the angles' 

 at which they are to be placed is as follows: The pulleys 

 which are to be connected by a belt are A and B, and they 

 have the relative locations as shown in the various views. 

 The center line XX in the elevation is prolonged, and at a 

 distance L (see plan) from the line ZZ through the middle 

 plane of the face of the pulley A, the line Z'Z' is drawn. 

 Through the point p, the line YY is drawn parallel to XX> 



