IMPROVEMENTS IN REVOLVING SHUTTERS AND IN MACHINERY POR PRODUCING THE SAME
Year: 1862

page_text: LETTERS PATENT to Joseph Bunnett, of Deptford, in the County of Kent,
Engineer, for the Invention of "IMPROVEMENTS IN REVOLVING SHUTTERS
AND IN MACHINERY POR PRODUCING THE SAME."
Sealed the 3rd October 1862, and dated the 12th April 1862.
PROVISIONAL SPECIFICATION left by the said Joseph Bunnett at the
Office of the Commissioners of Patents, with his Petition, on the 12th
April 1862.
I, JOSEPH BUNNETT, of Deptford, in the County of Kent, Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN REVOLVING
SHUTTERS AND IN MACHINERY FOR PRODUCING THE SAME," to be as follows:-
These revolving shutters are so constructed that they can also be used as
venetian blinds. For this purpose each lath is mounted on a central axis,
which moves up and down in the guiding shutter grooves, the upper edges of
the laths are connected together by hinged flaps. A portion of the inner
side of each shutter groove turns on pivots, and when it is desired to use the
shutter as a venetian blind, this limb of the groove is turned a quarter round,
when the laths are free to turn on their axes and may be set at any required
inclination. The winding pulley used for raising and lowering the shutter is
fitted with a friction wheel or brake which is brought into action in lowering
the shutter, but runs free when the shutter is being wound up. In order to

page_text: give the required curve to the edges of the shutter laths, a bending machine
is used by means of which both edges of the lath are simultaneously bent to
the proper form by dies acted upon by cranks or eccentrics, actuated by steam
or other power.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Bunnett, in the Great Seal Patent Office on the
11th October 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPи
BUNNETT, of Deptford, in the County of Kent, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of April, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Joseph Bunnett, Her special licence that I, the said Joseph
Bunnett, my executors, administrators, and assigns, or such others as I,
the said Joseph Bunnett, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN REVOLVING SHUTTERS AND IN MACHINERY FOR PRODUCING THE
SAME," upon the condition (amongst others) that I, the said Joseph Bunnett,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same was
to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said Joseph Bunnett, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
thereof, that is to say :-
These revolving shutters are so constructed that they can also be used as
venetian blinds. For this purpose each lath is mounted on a central axis which
moves up and down in the guiding shutter grooves, the upper edges of the
laths are connected together by hinged flaps. A portion of the inner side of

page_text: "
each shutter groove turns on pivots, and when it is desired to use the shutter
as a venetian blind, this limb of the groove is turned a quarter round, when
the laths are free to turn on their axes and may be set at any required
inclination. The winding pulley used for raising and lowering the shutter is
fitted with a friction wheel or brake, which is brought into action in lowering
the shutter, but runs free when the shutter is being wound up. In order to
give the required curve to the edges of the shutter laths a bending machine
is used by means of which both edges of the lath are simultaneously bent to
the
proper form by dies, acted upon by cranks or excentrics actuated by steam
or other power.
And in order that the nature of my said Invention and' the manner of
performing the same may be more fully understood, reference is had to the
annexed Drawings, and to the following description thereof:-
Figure 1 is a front elevation of a shutter constructed agreeably to my
said improvements; Figure 2, a side section of the same; Figure 3 is a full
sized section of the shutter closed, and Figure 4, a full sized section of the
same open as a venetian blind. The same letters refer to similar parts in
each of these Figures.
A, A, are the laths, each of which bas a projecting central axis a at each
end, B, B are flat hinges, jointed at their upper ends to the shutter roller A²,
and also to the upper parts of each of the laths at b. The axes of the laths
slide up and down in grooves at the sides of the window. Figure 5 is a
plan view of one of these grooves, the part marked C, is fixed, but the part
D is moveable on the centre d; E is a vertical bar of iron moving on guide
pins e. Attached to the lower end of the moveable limb D, there is an
inclined rising step or quadrant, upon which the foot of the vertical bar E
rests, its fore edge laying flush with the back of the groove. When the
shutter is to be used as a venetian blind, it is lowered and the limb D turned
round a quarter of a revolution into the position shewn in Fig. 5, and by the
dotted lines in Fig. 5, when the bar E will be lifted by the rising step before
described, and by means of the guide pins e, working in the inclined slots f.
the bar will be thrown forward, when the notches g in the front edge of the
bar, come in contact with and form bearings for the axes a of the laths,
which may then be set at any required angle, by means of a handle attached
to the lower bar or rail of the shutter. When the shutter is to be closed, the
limb D is turned back into its original position, the bar E then falls back into
its place, flush with the back face of the groove. Figure 6 shews another
mode of actuating the bar E; in lieu of the rising step herein-before described,
a cam H is placed at the lower part of the groove.
When the shutter is

page_text: lowered, the axes of the lowermost lath a comes down upon and by its weight
depresses the point h of the cam, which causes the opposite point i to rise
and lift the bar E upward and forward, the lathes may then be opened as
required. On beginning to wind up the shutter, the cam H and the bar E
fall back into their original positions.
Figure 7 is a front view, and Figure. 8 is a side section of the apparatus
for raising and lowering these (or any other) revolving shutters; K is the
lower step or bracket with a fixed spindle ; L is a chain wheel; 1, 1, an
endless chain which passes round under the wheel L, and up over a cor-
responding wheel on the shutter roller A2; M is a ratchet wheel, having a
groove on its inner face for the reception of a thick ring of leather or other
suitable material, to form a brake m, which is pressed against the inner
surface of the chain wheel L, the pressure being regulated by a tightening
nut n, according to the amount of retarding power that is required; O is a
pay that takes into the ratchet wheel M; P is a spur wheel keyed on to the
chain wheel L, and gearing into a pinion Q, to the axis of which the winding
bandle is applied. In the case of small shutters, however, this toothed
gearing may be dispensed with and the winding handle applied direct to the
chain wheel L; while the shutter is being wound up the chain and ratchet
wheels move together, the ratchets lifting and passing freely under the pawl.
But when the shutter is being lowered the pawl O, takes hold of the ratchet
wheel and prevents it from turning, consequently the chain wheel is acted
upon by the brake m, which relieves the winding handle of a portion of the
weight, and prevents the shutter from running down too fast. A piece of
hard wood or thick leather is affixed to the under side of the pawl and runs
in a groove in the edge of the ratchet wheel, so as to keep the pawl from
striking upon it, by which means a noiseless action is obtained. A key piece
9, affixed to the step or bracket K, takes into the grooved edge of the ratchet
wheel M, and keeps the winding apparatus in its place on the spindle k.
Figure 9 is a front elevation; Figure 10 an end elevation, and Figure 11
a cross section of a machine for giving the required curvature to laths for
revolving shutters; A, A, is the frame or standard of the machine, B a pulley
to receive motion from a steam engine or other prime mover, which is trans-
mitted by means of a pinion b, and toothed gearing to the several parts of
the machine for the operations as herein-after described. In the first instance
the two longitudinal edges of the lath are slightly bent by being brought up
against a die c, on a rocking shaft c', which is moved backward and forward
by an arm d, and connecting rod d³, actuated by cranks on disc wheels E at
each end of the machine. The two edges of the lath being thus slightly bent,

page_text: the one up and the other down, the lath is fed into the machine at H, and is
guided on to a bed plate I. Above this bed plate there is a block of metal J,
working up and down in guides at the end of the machine, being lifted by
cams j, j, on the revolving shaft J. As soon as the lath has been placed
upon the bed plate I, the metal block or holder J comes down upon it, thé
pressure being increased by the action of two wipers K, K, on the revolving
shaft J, which take a bearing upon feather plates k, k. While the lath is
thus firmly held upon the bed plate, the revolution of two crank shafts 1, l',
actuated by the toothed wheels L, L, forces the die holders M and dies m,.m²,
towards two corresponding dies, m³, mt, one of which is fixed to the bed plate
I, the other to the hold-down J. The consequence of this is that the edges
of the laths are bent into a curvilinear form to any extent that may be
required.
Figure 12 is an enlarged view of the dies and lath in its finished state; the
dotted lines shew the form of the lath after the first preliminary bending, in
which state it is fed into the finishing part of the machine. In this figure it
will be seen that the upper die m³ is hinged to the hold down J, for the purpose
of enabling it to leave the finished lath without injury. As the revolution of
the cranks 1, causes the die blocks to recede, the finished lath falls out to
make room for the insertion of the succeeding one. By regulating the
distances of the dies any required amount of curvature may be given to the
edges of the lath from a portion to the whole of a circle.
In witness whereof, I, the said Joseph Bunnett, have hereunto set my
hand and seal, this Tenth day of October, in the year of our Lord
One thousand eight bundred and sixty-two.
Witness,
W. BADDELEY,
Patent Agent,
Islington.
JOSEPH BUNNETT. (L.S.)