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The contributor feels that, to fully appreciate the ingenuity of Mr Carter's
invention, some generalities on change ringing are neccesary, and, therefore,
prefaces the description with the following details.
Change ringing, in brief, is the art of ringing changes by commencing from
"rounds" (1, 2, 3, 4, 5, 6), and re-arranging each successive row by a
pre-determined method, until the bells ultimately assume their first position,
i.e., "rounds."
There are numerous "methods," each governed by definite rules and
known by a certain name, such as "Plain Bob," "Grandsire," etc.
The total number of changes on a given number of bells is termed the
"extent," and is obtained by multiplying the numbers together; thus the
extent on 3 bells = 1 x 2 x 3 = 6, and so on.
A "Peal" consists of not less than 5,040 changes on any number of bells.
The peals rung on given numbers of bells are named as in the Table on
page 264,[see below] the "extent" being given also.
Thus one would speak of "Grandsire Triples" or "Bob Royal."
By rearranging each row in the simplest order, the bells "come into rounds"
in a number of changes equal to twice the number of bells being rung;
therefore other steps have to be talken to prevent this if it is desired
to ring a peal.
These steps are termed "place making" and "dodging"; bells not
doing this are referred to as "hunting."
"Place making" is striking two blows in one position (other than
"leading" or being "behind").
"Dodging," i.e., successive alternate blows, rather more
difficult to explain.
Even this form of dodging and place making does not suffice on larger
numbers of bells, and the aid of "bobs" and "singles" have to be
invoked.
It is not neccesary, however, to go further into the intricacies of
change ringing, as it should be obvious to all that Mr Carter set himself
no mean task when he conceived the notion of making a mechanical apparatus
to do what hitherto had required one alert mind for each bell in the peal.
No of |
Bells |
Title |
|
Extent. |
4 |
bells |
Singles |
24 |
changes |
5 |
,, |
Doubles |
120 |
,, |
6 |
,, |
Minor |
720 |
,, |
7 |
,, |
Triples |
5040 |
,, |
8 |
,, |
Major |
40,320 |
,, |
9 |
,, |
Caters |
362,880 |
,, |
10 |
,, |
Royal |
3,628,800 |
,, |
11 |
,, |
Cinques |
39,916,800 |
,, |
12 |
,, |
Maximus |
479,001,600 |
,, |
|
|
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A course of Stedman Caters
(9 bells and Tenor Governing)
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A course of Kidderminster Royal
(10 bells)
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Stedman Slow Course
(5 bells)
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We may now proceed with the description of Mr Carter's invention.
Carter's "Campanamutophone" or Ringing Machine
Mr. Carter and his Change Ringing Machine.
This machine actuates a battery of gongs, causing them to ring or
strike in any desired order, either in plain sequence or in the
manner know as "change ringing." In this latter, as practised on
church bells, the changes continually vary with each "round" or
sequence, the paths of the bells being interlaced in a varying and
often very intricate way.
The gongs, once placed on top of the machine and struck mechanically,
are now controlled by electrical contact, each of the 12 being
connected with a wire to its companion plate upon the machine.
They may at times be rung at the side of the machine or at any
distance from it.
The machine itself is designed with the utmost compactness and
efficiency. It is about 24 ins. in length, 10 ins. in width and
7 ins. in height.
It is made in two tiers and seated upon a box, within which is
a small motor.
From the latter, by the neccesary gearing, the machine is made to
ring about 28 "changes" per minute.
The lower tier contains, as it were, the "brains" of the directing
mechanism, and the upper tier contains the twelve plates which move
transversely or across the machine, and which lie in the order
or sequence to which the machine has been set to work.
Each plate moves notch by notch into twelve "places" according to the
term as used in "ringing".
In each of these it will cause its own gong to strike once, and on
being set, the plates will strike twelve different places or one
"change".
The next movement of the controls will cause the plates to either
move on or back one notch or to lie still.
In This way successive "changes" will be produced according to the
setting of the machine.
The principle of the lower part of the machine is as follows,
viz.: The main shaft is driven from below, and consists of
a sort of skeleton cylinder of 12 rods, these will be referred to later;
it has also geared wheels at each end, one of which receives the drive
from below, and is fitted with a friction safety device, and the other
wheel drives the second shaft, and through it the third.
It is fitted at the end with a revolving "snail" or cam, the purpose of
which is to oscillate a pair of control-boxes at the fron end of the
machine.
There is another somewhat similar on each side just within the others,
the purpose of which is to oscillate two long connecting levers which
join up and co-ordinate the front control boxes with the control
cylinders at the back.
Thus it will be observed that when the main shaft or cylinder revolves,
it carries with it twelve concentric rods, oscillates the front control
boxes and also causes them to have a to and fro motion governed by the
control cylinders.
The second shaft referred to above has for its purpose the driving of
six rods attached to it by eccentrics, these by cranks cause eleven long
rods to work to and fro engaging over the top of the cylinder and
reaching along to the front of the machine.
The third shaft is principally for causing a contact crank to revolve
round a square dial, set with pins in concentric rows according to the
number of gongs or bells desired to be rung, the crank being fitted
with an adjustable contact piece.
Thus as it travels round it makes electric contact for two "changes."
The more intricate part of the lower tier, however, now calls for
description, viz., the controls. Taking these separately:-
The control boxes:
These are square shallow boxes fitted with movable pins, of these
there are 15 rows and there are 6 pins in each row.
Thus a box contains 90 pins and each pin is capable of being put into
three positions of control in respect to further pins or levers below.
Consequently, as these boxes rise or fall, or travel to and fro, as
previously described, they either avoid or they press down the ends
of the levers below. The pins are set according to the number of bells
and according to the particular "method" desired to be rung.
The control-cylinders: These are at the back of the machine, and work
with the boxes.
They are fitted with 48 adjustable slides, and according to the length
to which they are set so does the "throw" of the two long connecting
levers vary.
These rods, like the pins, are set for the number of bells and for the
"method."
The skeleton cylinder is the means whereby the above control action is
passed on to the upper tier of the machine.
Its machanism is very elaborate.
It consists of 12 rods each fitted with a controlpin and with a
lifting cam with which it does the work it may be called upon to do.
Each rod has also a lateral action, and according, as the pins are
deflected either to the left or right, so the rod is moved laterally
and the cam brought into play or not as is required by the particular
case of setting.
The linking up of the controls above outlined is as follows: There are
12 cranked levers below the boxes, and with ends turned up to engage
with the control pins.
As these are depressed they elevate corresponding arms at the back,
at the top of which arms are the rocking heads and short horizontal
rods into which they engage with small pins.
Thus as an arm comes up its pin imparts a small rotation to the
horizontal rod, there being a small scoop-shaped funnel at the
other end of this rod, it follows that it can control and impart
lateral movement to any pin passing through it. The pins passing through
are those described as being on the cylinder rods, and as these funnels
are capable of being either right, middle or left, so is the
cylinder controlled in its work.
The principle of the upper part of the machine is as follows, viz.:
Below are 11 long rods or levers capable of moving to and from.
They engage by double "clicks" with 12 plates, to which they impart
movement, but at right angles to themselves.
The rods or levers are immediately above the companion ones previously
referred to, and it is from these that they get their impulse.
As the latter move to and from they, in a normal position,
clear the upper rods, but as soon as the cylinder cam lifts a rod,
then it engages with the one above by means of a lug which rises into
a slot on the underside of the top rod, which has then to conform to
its motion and regains its position by means of a spiral spring.
Insulated from the rest of the machine and on top is a long board
carrying 12 metal strips each insulated form the other.
The plates make contact with these by means of a small pillar which
rises from the bed of each.
Thus as the plates traverse notch by notch the various places it has
to make, it carries its pillar and passes it successively over the
different strips, and with each contact the gong working with that
particular plate strikes once.
The above was published in "Model Engineer" in 1925. I have copied
the text, but the layout may be somewhat different! The photos are
extracted from a scan of the original text.
The images of peals are produced by the machine which has a device
for drawing a chart showing the course of one bell in a peal.
By Bill Purvis - 13th October 2010
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