Chapter IV: Section 3: Belt Gearing

Materials employed are:--Leather, cotton, guttapercha, indiarubber,
canvas, camel-hair, catgut, flat wire or hemp rope, steel bands, flat
chains, &c.

=22. Ordinary belt pulley,= “crowned” on face to retain the belt on the centre of the pulley.

=23. Double-flanged pulley,= flat on face, sometimes “crowned,” as No. 22.

=24. Single-flanged pulley= for horizontal driving.

=25. Open belt gear;= runs best as shown, with the slack half of the belt at top.

=26. Crossed belt= to reverse motion on the driven shaft. Also to obtain more grip for the belt than with open belts.

=27. Mode of driving= when the shafts are at right angles to one another.

=28. Mode of driving= with shafts at an obtuse angle, sometimes used instead of bevel wheels.

=29. Arrangement adopted when the pulleys cannot be got in line= with one another, or the shafts are too close together to drive well direct. Short belts seldom work well.

Belts are frequently arranged to pass under and over several pulleys
so as to drive several shafts by one belt.

For reversing by belt gear, see Section 74. Gut bands (round) are
worked over ~V~-grooved pulleys; see Rope Gearing, Section 66. Belts
may be kept tight by tightening pulleys, see No. 1207. For round
belts, see Rope Gearing, Section 66. ~V~-belts are occasionally used,
formed of thicknesses of leather riveted together, cut to a
~V~-section, and worked over ~V~-grooved pulleys.

Section 4.--BALL-AND-SOCKET JOINTS.

=30. Universal hinge.= The arm can be fixed in any required position by tightening the gland. Useful for stands for articles to be exhibited in any position, telescopes, &c.

=31. Pipe joint,= with similar capabilities.

=32.= Same as No. 16, but with screwed gland. If used without the arm, it forms the ordinary ball castor.

=33 & 34. Dr. Hooke’s universal joint.= See application, No. 292. See also Nos. 1359 and 732.

Gas pendants are suspended with a joint similar to No. 31, but the
ball, having only a restricted angular motion, is cut down to a
segment only.