These are the definitions we use here in this journal. Many of them are standard. Some of them are not.
Some of these are called different names in different parts of the world.

Verge:			also called  anchor, pallet,  or escapement

Chime:			also called  chimes, gong, melody

Gong Rod:		also called  chimes, gong, strike

Main wheel		also called  great wheel, spring barrell

Second wheel		this means the wheel next to the Main wheel. We generally assign numbers to each 
			wheel, up from the bottom of the gear train, to refer to that wheel. 

Centerpost		this means the post the minute hand fits on 

Centerpost gear		this means the gear on the centerpost ( sometimes called the 3rd wheel )

Hour tube		the sleeve that the hour hand fits on

Pendulum		also called  pendulum ball, pendulum bob

Suspension		also called the suspension arm. The pendulum is attached to this part. When a user
			"puts the pendulum on the clock," this is what it is usually attached to. 

Suspension spring	this means the spring that the suspension hooks to that provides recoil for the
			swing of the pendulum

Suspension post		this means the post that the suspension is hooked to

Adjusting nut		this means the nut at the bottom of the pendulum bob that allows for timekeeping 
			adjustments. (The adjusting nut is not always at the bottom of the pendulum.)

Strike			The sound the clock makes when it counts the hour. Do not confuse this with the 
			melody.

Ratchet wheel  		Part of the mainspring ratchet assembly. The ratchet wheel is a gear, with a square
			opening in the center that fits the mainspring arbor precisely. This gear usually
			has slanted teeth with valleys that fit the end of the click (ratchet dog)
			precisely, thus keeping the mainspring from releasing and destroying, gears,
 			person's fingers, and other clock parts. This is the device that holds the 
			mainspring tight after each turn of the key. When fully wound, this device has the 
			full power of the mainspring on it. The stored energy ( potential energy ) of the
 			mainspring is held by the one single active tooth on this wheel in conjunction with
			the ratchet dog. Failure at this point causes massive damage.  

Click			Part of the mainspring ratchet assembly. The click is often called the ratchet dog.

Click spring		Part of the mainspring ratchet assembly. The click spring causes the click (ratchet
			dog) to snap into the valleys of the ratchet wheel.

Maintaining hook	A hook that holds a spring tight inside the main wheel of many weight drive clocks.
			This spring applies pressure in a reverse direction to the pull applied by winding.
			The reason for this is that when the clock is wound while it is running the power
			to the gear train is briefly interrupted which makes the escape wheel stop. 
			Occasionally the verge will then come down right on top of one of  the teeth of the
			escape wheel, causing it to be bent. With the spring and maintaing hook in place 
			and  functioning correctly, enough pressure is maintained on the escape wheel while 
			winding the clock to prevent damage by keeping just enough power to the escape wheel
			to keep it from stopping.

Isochronal error	A fancy way of saying a mainspring has more power when it is fully wound, than when
			it is run down. The power curve of a mainspring is non-linear, thus resulting in 
			timekeeping errors. ( see the section in trouble shooting more info ). 

Fusee ( Fuzee ) 	A design by which the power from the mainspring of a clock is delivered to the rest
			of the system through a spiral cone shaped spool with grooves for the cable. The 
			top end of the mainspring power is delivered to the smallest diameter of  the fusee.
			This reduces the ampount of power delivered because of the difference in diamters.
			The bottom end of the mainspring power is delivered to the largest diameter of the 
			fusee. This increases the amount of power available with respect to the top end, 
			thus effectively eliminating the effect of isochronal error by mechanically 
			equalizing the power delivered by the mainspring.

Platform escapement	Usually found in ships bell clocks, and expensive french carriage clocks. This 
			usually consists of a balance wheel and associated parts, a verge which is often 
			jeweled, and an escape wheel. The design of these balance wheels is very similar
			to what is found in large pocket watches. Some of the higher quality balance
			wheels have timekeeping adjustment screws in the wheel itself.

Sequence		The sequence of the operation of the gears and / or hammers and / or shutoff and 
			/or trip levers  of a particular section of a mechanism to produce the correct
			result of sound or mechanical operation.


Top end power		Fully wound mainspring.

Bottom end power	Mimimum mainspring power. Power delivered at the "almost totally unwound state"
			of a mainsping's power curve.  

Back to Notes From The Bench index

Page by: Perpetual PC's

---

Copyright (c) 2002 David Tarsi. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with the Invariant Sections being no invariant sections, with the Front-Cover Texts being no Front-Cover Texts, and with the Back-Cover Texts being no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".