IMPROVEMENTS IN WEIGHING MACHINES
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHRISTOPHER
EDWARD DAMPLER, of Ware, in the County of Hertford, Gentleman, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing. date at West-
minster, the Fifteenth day of April, in the fourth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Christopher
Edward Dampier, Her especial licence that I, the said Christopher Edward
Dampier, my exors, adññiors, and assigns, or such others as I, the said
Christopher Edward Dampier, my exors, adiñors, or assigns, should at any
time agree with, and no others, from time to time and at all times during the
term of years therein expressed, should and lawfully might make, use, exerciso
and vend, within England, Wales, and the Town of Berwick-upon-Tweed, and
also in all Her said Majesty's Colonies and Plantations abroad, my Invention
of IMPROVEMENTS IN WEIGHING MACHINES;" in which said Letters Patent is
contained; a proviso obliging me, the said Christopher Edward Dampier, by an
instruinent in writing under my hand and seal, particularly to describe and
ascertain the nature of my said Invention, and in what manner the same is to
be performed, and to cause the same to be enrolled in Her said Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by tho
same, reference being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Christopher Edward Dampier, do hereby declare the nature of my said Inven-
tion to consist,—
First, in a peculiar mode of applying a spiral spring as the resisting power
in certain weighing machines.
Second, in the application of a spiral line of graduation with a sliding index
following a corresponding spiral course for weighing machines.
Third, in the application of diagonally-cut toothed wheels for multiplying
wheels to weighing machines.
Fourth in the application of revolving or moveable bearings to knife-edged
or other fulcra, and for the fulcra of the scales or weight supporters of
weighing machines; and,
Fifth, in a mode of adjusting scale bearers and levers by means of end
screwed balance weights or bearings. And in further compliance with the said
proviso, I, the said Christopher Edward Dampier, do hereby describe the
manner in which my said Invention is to be performed by the following
statement thereof, reference being had to the Drawing annexed, and to the
figures and letters marked thereon, that is to say:-
DESCRIPTION OF THE DRAWING.
Figure 1 represents a front view of my first improvement, being a spiral
spring, the inner extremity of which is fastened to a fixed point as to the
cross frame at a, while its outer extremity is fixed to a pulley wheel B, over
which the cord which supports the scale passes; it is scarcely necessary to
observe, that the index hand is fastened upon the spindle or axis of the pulley
wheel; and Figure 2 is a side view of a similar spiral spring, with this
difference, that the inner end of the spring, in this case, is fastened to the
axis of the pully wheel, while the outer end is fastened to a fixed point on
the frame.
Figure 3 represents my second improvement, being a front view of the dial
of a weighing machine, having its graduations on a spiral line; and in order to
make the index follow a similar spiral course, I cast the ribbed spiral C on
the dial, and allow the hand or index to pass through a circular rib or loop e,
projecting from the axis of the revolving pully behind the dial. I also furnish
the index at D with two friction rollers, one acting against each side of the
spiral rib. By this arrangement it will be evident that as the hand or index
inoves round one way or the other, so will it be moved gradually out or in
in its progress round to meet the graduated spiral line.

page_text: Figure 4 represents my third improvement, applied to the index of a. beam
weighing machine. I is a diagonally, cut; toothed wheel, fixed at G, G, to
the scale beam; H, H and I is a diagonally cut toothed pinion, working, in tho
To: the axis of this pinion. tho hand, or index. J is fixed, and thus a
small motion of the beam causes a wide range, to the index...
same.
Figure 5 is a section, shewing, the mode of first adjusting. the index by
screwing the screw K against the axis of the pinion, which is resisted by the
spring L, and thus enables a very correct adjustment, to be; made.:
But to return to, Figuro 4, which: also; represents, several of my improved
or moveable fulcra for weighing machines, being my fourth improvement. M
represents a wheel having a segment removed from, its upper, part,, in which
anknife-edged axis of the scale, link. N. rests. This wheel. M moves, quite
loosely in the circular, aperture cut for it in, the, scale,beam, and, thus, forms
a moveable bearing: At the other end of the;beam,; P Prepresents another.loose
wheel, through the centre of which, the scale link. passes, doing away, with the
knife edge... R is the knife-edged axis of the scale beam itself, the; axis being
circular at S, and turning loosely in the scale beam serves the purpose: of, the
wheels M and P.
Figure 6 represents an end view of another modification of the same, thing,
the circular part of the axis; S, turning loosely in the scale beam,, while.. the
knife edge is a:fixed point beneath..
T and W, in Figure.4,, represent.my, fifth improvement, and are 2 adjusting
screwed balance.weights, which by, screwing in or out adjust the true balanco
of the beam, the points. at which the scales are, hung, remaining, always
equidistant from the centre; and I apply the same end screw to adjust the
proportionate distances between the bearings of lever beams by using the
periphery of the screw head, as shown at Z in Figure. 2, as one of such knife-
edged bearings.. Another of my moveable bearings, which I class under my
fourth head of improvement, is shown. at Figure 1, in order not to multiply
Figures in the Drawing; but as it acts on a principle different entirely from
the others, I have thought it best to reserve a separate description for it.
The axis of tho pully in this might be supposed, on a careless inspection, to
rest on the cross frame through which it protrudes to receive the hand or
index; but it is not so, the axis of the pully resting, in fact, upon the lower
sweep of the pendulous quadrant x, a, the axis being confined by the frame
laterally. This quadrant is suspended above the pully on an ordinary knife-
edged axis, as shewn at Y, and as the axis of the pully wheel B turns round,
it rolls along the lower sweep of the quadrant, thus avoiding much friction.

page_text: Now whereas, I claim as my Invention the following improvements,―
First, the application of the spiral spring to weighing machines, as shewn
in Figures 1 and 2.
Second, the application of a spiral line of graduation, and corresponding
movement of the index to weighing machines, as shewn at Figure 3.
Third, the application of diagonally cut toothed multiplying wheels to the
axis of the index of weighing machines.
Fourth, the moveable bearings and arrangement of knife-edged fulcra,
connected with the same, as applied to weighing machines, and described in
Figures 4 and 1; and,
Fifth, the adjusting screws, as applied to scale beams, and shewn at T, W,
And such my
in Figure 4, and to levers as shewn at Z in Figure 2.
Invention being, to the best of my knowledge and belief, entirely new, and
never before used within that part of Her said Majesty's United Kingdom of
Great Britain and Ireland called England, Her said Dominion of Wales, or
Town of Berwick-upon-Tweed, nor in any of Her said Majesty's Colonies and
Plantations abroad, I do hereby declare this to be my Specification of the
same, and that I do verily believe this my said Specification doth comply in
all respects, fully and without reserve or disguise, with the proviso in the said
herein-before in part recited Letters Patent contained; wherefore I hereby
claim to maintain exclusive right and privilege to my said Invention.
In witness whereof, the said Christopher Edward Dampier hath hereunto
set his hand and seal, the Fourteenth day of October, in the year of
Our Lord One thousand eight hundred and forty-one.
CHRIS EDW. DAMPIER. (L.S.)
AND BE IT REMEMBERED, that on the Fourteenth day of October, in
the year of our Lord 1841, the aforesaid Christopher Edward Dampier came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.
Inrolled the Fifteenth day of October, in the year of our Lord One