Читать книгу The Modern Clock. A Study of Time Keeping Mechanism; Its Construction, Regulation and Repair онлайн
6 страница из 100
The German clocks are generally those of the Schwartzwald (or Black Forest) district, and differ from others in their structure, chiefly in the following particulars: The movement is supported by a horizontal seatboard in the upper portion of the case. The wooden trains of many of the older type instead of being supported by plates are held in position by pillars, and these pillars are held in position by top and bottom boards. In the better class of wooden clocks the pivot holes in the pillars are bushed with brass tubing, while the movement has a brass ’scape wheel, steel wire pivots and lantern pinions of wood, with steel trundles. In all these clocks the front pillars are friction-tight, and are the ones to be removed when taking down the trains. Both these and the modern Swartzwald brass movements use a sprocket wheel and chain for the weights and have exposed pendulums and weights.
The French clocks are of two classes, pendules and carriage clocks, and both are liable to develop more hidden crankiness and apparently causeless refusals to go than ever occurred to all the English, German and American clocks ever put together. There are many causes for this, and unless a man is very new at the business he can tell stories of perversity, that would make a timid apprentice want to quit. Yet the French clocks, when they do go, are excellent timekeepers, finely finished, and so artistically designed that they make their neighbors seem very clumsy by comparison. They are found in great variety, time, half-hour and quarter-hour strike, musical and repeating clocks being a few of the general varieties. The pendulums are very short, to accommodate themselves to the artistic needs of the cases, and nearly all have the snail strike instead of the count wheel. The carriage clocks have watch escapements of cylinder or lever form, and the escapement is frequently turned at right angle by means of bevel gears, or contrate wheel and pinion, and placed on top of the movement.