Difference between revisions of "Bell Ringing Components"

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== Mechanical Components ==
== Mechanical Components ==
[[File:Bell-swinging-annotated.png|frameless|right|300px|Swinging Bell Components]]
=== Bell ===
=== Bell ===


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==== Swinging Bell ====
==== Swinging Bell ====
[[File:Bell-swinging-annotated.png|frameless|right|300px|Swinging Bell Components]]
A swinging bell (A) is shown in the diagram with a wheel and electric hammer.
===== A-Stand and Headstock =====
A swinging bell is typically gimbal mounted to a headstock to allow free swinging. In the illustration the headstock (F) has welded on axles inserted to a pillow block style ball-bearing (H) that is attached to the top of the A-stand (B) which is designed to support the weight and swinging forces of the bell and transfer them to the tower structure (not shown).
===== Headpiece and Clapper =====
The bell is suspended from the Headstock with a headpiece (G) that distributes the weight of the bell evenly between the suspension bolts (E). The headstock for a swinging bell has a pivot from which the free swinging clapper (C) is mounted.


A swinging bell
===== Wheel =====


===== Headstock =====
Traditionally, pulling a rope attached to the wheel (D) rings a swinging bell. The wheel is attached to the headstock (F). Ropes will only allow the bell to be pulled in one direction. Chain or belt driven motors with position feedback can be used to pull in both directions.


A swinging bell is typically gimbal mounted to a headstock
For a cleaner visual aesthetic and quieter mechanical performance, modern [http://www.chimemaster.com/swinging-motors/ MagForce] induction motors do away entirely with the need for a wheel. Only an aluminum plate is mounted to the headstock. The motor, attached to the A-stand induces currents into the plate without physical contact.
 
===== Tolling Hammer =====
 
The lively sound of one or more bells swinging evoke a celebratory atmosphere. This is used for calling people to church or celebrating special events. When announcing times of prayer or mourning, a toll of the bell while it is stationary is more appropriate.
 
The diagram shows such a hammer (I) actuated by an electromagnet (J) that allows an [http://www.chimemaster.com/libertas electric bell control system] to sound the hour, announce prayer times or count the age of the person being memorialized.


==== Stationary Bell ====
==== Stationary Bell ====


=== Striker ===
=== Striker ===
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For stationary bells, the clapper is typically supported close to one ideal strike point and an externally applied force moves the head toward the bell for a single strike.
For stationary bells, the clapper is typically supported close to one ideal strike point and an externally applied force moves the head toward the bell for a single strike.
==== External hammer ====
==== External ram ====
=== Actuation System ===


== Electrical Components ==
== Electrical Components ==

Revision as of 15:53, 31 August 2016

Mechanical Components

Bell

The bell itself is the resonant portion of the system that provides a musical tone when struck. The General Campanology page provides a list of additional pages for further study into the physics of bells.

Suspension

In order to ring, the bell must be hung in such a way that it can freely resonate. Traditional bells are generally suspended from the top. This can be accomplished by simply providing holes for attaching bolts, or an optional crown top is provided for attachment.

Beams of wood or metal have been used for suspending bells. Wood has the advantage of being non-resonant. Double C-channel steel is often used to mount bells by placing the center bolts of the bell through the slot between channels. Tubular steel is the most unfavorable because of its resonant qualities that are detrimental to the sound of bells. Isolation materials must be used when multiple bells are suspended from the same beam to inhibit sympathetic vibrations.

Swinging Bell

Swinging Bell Components

A swinging bell (A) is shown in the diagram with a wheel and electric hammer.

A-Stand and Headstock

A swinging bell is typically gimbal mounted to a headstock to allow free swinging. In the illustration the headstock (F) has welded on axles inserted to a pillow block style ball-bearing (H) that is attached to the top of the A-stand (B) which is designed to support the weight and swinging forces of the bell and transfer them to the tower structure (not shown).

Headpiece and Clapper

The bell is suspended from the Headstock with a headpiece (G) that distributes the weight of the bell evenly between the suspension bolts (E). The headstock for a swinging bell has a pivot from which the free swinging clapper (C) is mounted.

Wheel

Traditionally, pulling a rope attached to the wheel (D) rings a swinging bell. The wheel is attached to the headstock (F). Ropes will only allow the bell to be pulled in one direction. Chain or belt driven motors with position feedback can be used to pull in both directions.

For a cleaner visual aesthetic and quieter mechanical performance, modern MagForce induction motors do away entirely with the need for a wheel. Only an aluminum plate is mounted to the headstock. The motor, attached to the A-stand induces currents into the plate without physical contact.

Tolling Hammer

The lively sound of one or more bells swinging evoke a celebratory atmosphere. This is used for calling people to church or celebrating special events. When announcing times of prayer or mourning, a toll of the bell while it is stationary is more appropriate.

The diagram shows such a hammer (I) actuated by an electromagnet (J) that allows an electric bell control system to sound the hour, announce prayer times or count the age of the person being memorialized.

Stationary Bell

Striker

We use the term striker to describe an element with an arm and head that excites a percussive instrument to resonate when they contact one another with a blow of some force. Actuation of the striker, regulation of the force and mass of the head for various purposes are described below.

Hand held mallet

Used to play orchestral bells, gongs and metallophones, these mallets consist of sticks with heads of relatively soft materials.

Internal clapper

We refer to any striker that is mounted inside the bell as a clapper.

For free swinging bells, the clapper is usually mounted to a hinge near the top center of the bell, aligned with the swinging axis of the bell so that it can strike the bell both fore and aft. Gravity and the motion of the clapper pivot relative to the bell gimbal axis causes the free clapper to strike the bell in its distinctive ding-dong fashion.

For stationary bells, the clapper is typically supported close to one ideal strike point and an externally applied force moves the head toward the bell for a single strike.

Electrical Components

Actuators

Electronics

Power switching

Automation