IMPROVEMENTS IN THE CONSTRUCTION OF LOCKS."
Year: 1865

page_text: LETTERS PATENT to John Calvert, of the Strand, in the County of
Middlesex, Civil Engineer, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF LOCKS."
PROVISIONAL SPECIFICATION left-by the said John Calvert, at the Office
of the Commissioners of Patents, with his Petition, on the 30th May
1865...
I, JOHN CALVERT, of the Strand, in the County of Middlesex, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION OF Locks," to be as follows:-
This Invention relates to certain improvements in the construction of locks,
in which great simplicity is combined with extraordinary security. The
mechanism employed consists of one or more cog wheels in combination with
a circular plate or curtain having pallette-like teeth formed on the periphery
thereof, such curtain being placed parallel to or in the same plane with the
cog wheels, and actuated by the key from the exterior of the lock. In the

page_text: description herein-after contained four cog wheels are supposed, for the
purposes of "explanation, to be employed. Each of the cog wheels is con-
structed with gatings on the periphery thereof formed by the removal or omission
of two of the cogs, so as to allow the teeth of the before-mentioned curtain
(which would otherwise take into the cogs) to pass across the wheels without
interruption. Parallel with each of the cog wheels and on the same spindle
is a wbeel furnished with ratchet teeth, and a detent or catch kept in position
by a spring in the ordinary manner, such ratchet wheel being connected with
and actuated by a stud or other analogous arrangement on the face or exterior
of the lock. A portion of the periphery of the ratchet wheel is constructed
with a blank or without teeth, and a pin is attached thereto so as to be capable
of being placed between any two of the cogs of the wheel with which it is
connected. The bolt plate is carried backward and forward by the before-
mentioned curtain by means of a pin attached to the latter, and which pin
works in a slot formed in the bolt plate. By a simple modification two or
more bolts may be actuated in different directions by the use of additional
pins and slots. The ratchet wheels are in the first instance set to the cog
wheels by means of the pins before mentioned, and upon so arranging the cog
wheels that their gatings in their peripheries will coincide with the circum-
ference of the curtain, the latter may be turned without interruption by means
of the key, and thus shoot or withdraw the bolts. This may be considered
as the normal condition of the lock. If, however, one or more of the wheels
be turned to the extent of one or more cógs, beyond the blank or blanks upon
the ratchet wheel or wheels, as will be known by the click or clicks given by
the ratchet arrangement, the teeth of the curtain will be locked, and the latter
will be no longer capable of being turned in either direction, until the wheel
or wheels is, or, are restored to the original. position. It is manifest that a
great variety of combinations can thus be brought into requisition, thereby
affording the most perfect security; for even if the key be left in the lock, or
permanently fixed thereto, it will be impossible for any one to discover the
combination employed, and without a knowledge of which the lock cannot be
opened.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Calvert, in the Great Seal Patent Office on the
30th November 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
CALVERT, of the Strand, in the County of Middlesex, Civil Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of May, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Calvert, Her special licence that I, the said John
Calvert, my executors, administrators, and assigns, or such others as I, the
said John Calvert, 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
THE CONSTRUCTION OF LOCKS," upon the condition (amongst others) that I, the
said John Calvert, 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 John Calvert, do hereby declare the
nature of do hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained in
and by the following statement, reference being bad to the Drawings hereunto
annexed, and to the figures and letters marked thereon (that is to say): -
My said Invention consists of certain improvements in the construction of
Jocks, in which great simplicity is combined with extraordinary security. The
mechanism employed consists of one or more cog wheels in combination with
a circular plate or curtain having teeth or projections formed on the periphery
thereof, such teeth or projections being at right angles with the plane of the
plate or curtain. The said circular, plate or curtain is placed. parallel to or in
the same plane with the cog wheels, and is actuated by a key or analogous
contrivance from the exterior of the lock. In the description herein-after

page_text: contained, four cog wheels are assumed for the purposes of illustration and
explanation to be employed. Each of the cog wheels is constructed with
gatings in the periphery thereof, formed by the removal or omission of two of
the cogs, so as to allow the teeth or projections on the before-mentioned plate
or curtain (which would otherwise take into the cogs) to pass across the
wheels without interruption. Parallel with each of the cog wheels, and on
the same spindle, is a wheel furnished with ratchet teeth and a detent or catch
Kept in position by a spring in the ordinary manner, such ratchet wheel being
connected with and actuated by a stud or other analogous arrangement on the
face or exterior of the lock. A portion of the periphery of the ratchet wheel is
constructed with a blank or without teeth, and a pin is attached thereto, so as
to be capable of being placed between any two of the cogs of the wheel with
which it is connected. The bolt plate is carried backward and forward by the
before-mentioned circular plate or curtain by means of a pin attached to the
latter, and which pin works in the bolt plate. By simple modifications, which
will be apparent to and well understood by persons conversant with the
construction of locks, and' which do not affect the main principles of my said
Invention as herein described, two or more bolts may be actuated in different
directions by the use of additional pins and slots, and in cases in which bolts
of great weight are employed, a lever or levers may be substituted and used
in conjunction with or instead of the pin or pins, such lever or levers being
actuated by the key or other analogous contrivance used in lieu thereof. The
ratchet wheels are, in the first instance, set to the cog wheels by means of the
pins before mentioned; and upon so arranging the cog wheels that the gatings
in their peripheries will coincide with the circumference of the circular plate
or curtain, the latter may be turned without interruption by means of the key
or other contrivance, and thus shoot or withdraw the bolt or bolts. This may
be considered as the normal condition of the lock, in which state it may be
employed as an ordinary latch or lock. If, however, one or more of the
wheels be turned to the extent of one or more of the cogs beyond the blank
or blanks upon the ratchet wheel or wheels, as will be known by the click or
clicks given by the ratchet arrangement, the teeth of the circular plate or
curtain will be locked, and the latter will be no longer capable of being turned
in either direction until the wheel or wheels is or are restored to the original
position. It is manifest that a great variety of combinations can thus be
brought into requisition, thereby affording the utmost security, especially in
cases in which the locks are used as fastenings for places; or depositaries
Which are left unguarded at night; for even if the key be left in the lock, or

page_text: may be
permanently fixed thereto, it will be impossible for any one to discover the
combination employed, and without a knowledge of which the lock cannot be
opened. It has been before mentioned that instead of a key, an analogous
contrivance may be employed. For instance a follower may be attached to
the centre of the circular plate or spindle, the same terminating on the exterior
of the lock with a stud or handle. In like manner. the .cog wheels
provided with similar followers. Another mode of constructing such followers
is to make them of such an elongated form as to project beyond the face or
exterior of the lock, sockets being formed in the ends thereof for the admission
of a key, by which they may be actuated. A great advantage arising from
thus providing for the movement of the circular plate or curtain and the cog
wheels is, that no aperture is left in the face of the lock through which
gunpowder can be introduced.
I will now proceed to refer to and explain the annexed Drawings, from
which the nature of my said Invention will be more clearly understood.
Figure 1 is the bolt plate, the circular plate or curtain a being shewn in
dotted lines; b is the pin attached to the latter working in the slot c; d is a
stud or projection fixed to the lock, the same passing through the slot e in
the bolt plate, and serving as a guide for the same. Figure 2 shews the cog
wheels and the circular plate or curtain in position, so that the teeth of the
latter can pass through the gatings in the former; a is the curtain; b is the
pin thereon for actuating the bolt plate; c, c, c, c, are the cog wheels, and
d, d, d, d, are the detents or catches acting on the ratchet wheels. Figure 3
is a ratchet wheel and detent shewn detached, a being the pin which is
placed between the teeth of the cog wheel as before mentioned; Figure 4 is
the circular plate or curtain in correspondence with the gatings of the cog
wheel, also shewn. Figure 5 is the curtain with the teeth thereof in non-
correspondence with the gatings of the cog wheel. Figure 6 is an edge view
of the circular plate or curtain..
Having thus described and ascertained the nature of my said Invention,
and the manner in which the same is. to be performed, I. would observe, in
conclusion, that I do not claim the several and distinct parts of the mechanism
herein-before described. separate and apart from each other as being of my
Invention, and that I do not restrict or limit myself to the precise details
5 berein-before mentioned, as variations. may be made therefrom without
departing from the main features or principles of my said Invention, but what
I consider novel and original, and therefore claim as constituting the said
Invention secured to me by the said herein-before in part recited Letters
Patent is,

page_text: The combination and arrangement of mechanism for the construction of
locks substantially herein-before set forth and described, or any mere modifi-
cations thereof...
In witness whereof, I, the said John Calvert, have hereunto set my
hand and seal, this Thirtieth day of November, in the year of our
Lord One thousand eight hundred and sixty-five.
Witness,
E. P. H. VAUGHAN,
54, Chancery Lane,
Agent for the Patentee.
JOHN CALVERT. (L.S.)