CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF LOCKS AND LATCHES, SPINDLES AND KNOBS, APPLICABLE TO DOORS AND OTHER SIMILAR PURPOSES
Year: 1844

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
PITT, of George Street, York Street, Westminster, in the County of Mid-
dlesex, Machinist, send greeting.
.
WHEREAS I did, by petition, humbly represent unto Her present most
Excellent Majesty Queen Victoria that I had invented "CERTAIN IMPROVEMENTS
IN THE CONSTRUCTION OF LOCKS AND LATCHES, SPINDLES AND KNOBS, APPLICABLE TO
DOORS AND OTHER SIMILAR PURPOSES," and Her said Majesty being willing to give
encouragement to all arts and inventions which may be for the public good,
was graciously pleased, by Her Royal Letters Patent under the Great Seal
of the United Kingdom of Great Britain and Ireland, bearing date at West-
minster, the Fourteenth day of May, One thousand eight hundred and forty-
four, in the seventh year of Her reign, for Herself, Her heirs and successors,
to give and grant unto me, the said Benjamin Pitt, my exors, adiñors, and
assigns, Her especial licence, full power, sole privilege and authority, that I
or they, by myself or themselves, or by my or their deputies, servants or
agents, or such others as I or they should agree with, and no others, during
the term of fourteen years from the date of the said Letters Patent, should and
lawfully might make, use, exercise, and vend my said Invention within that
part of Her said Majesty's Dominions called England, Her Dominion of
Wales, and Town of Berwick-upon-Tweed, and in all Her Majesty's Colonies
and Plantations abroad, and in the Islands of Jersey, Guernsey, Alderney,
Sark, and Man, in such manner as to me, my exors, adiñors, and assigns, shall
seem meet, and as that I or they shall enjoy the whole profit and advantage

page_text: arising by reason of the said Invention during the said term of fourteen years;
and for that end Her said Majesty requires and strictly commands all Her
subjects whatsoever, within England, Wales, and Berwick-upon-Tweed, and
the Islands, Plantations, and Colonies aforesaid, that they shall not, neither
directly nor indirectly, make, use, or put in practice my said Invention, or any
part thereof, nor in anywise counterfeit, imitate, or resemble the same, nor
make
any addition thereto or subtraction therefrom, whereby to pretend himself
or themselves to be the Inventor or Inventors thereof: And whereas the said
Letters Patent contain a proviso obliging me, the same Benjamin Pitt, par-
ticularly to describe and ascertain the nature of my said Invention, and in
what manner the same is to be performed, by an instrument in writing under
my hand and seal, and to cause the same to be inrolled in Her Majesty's High
Court of Chancery within six calendar months next and immediately after the
date of the said Letters Patent, as in and by the same, reference being there-
unto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Benjamin Pitt, do hereby declare that my said Invention is described and
ascertained in manner following, and by the aid of the three Sheets of Draw-
ings hereunto annexed, that is to say :-
As to my improvements in locks and latches, the same consist in certain
means (herein-after particularly described) whereby one sliding bolt in the lock
is made to answer the double purpose of a spring bolt or latch, which will
fasten of itself when the door to which the lock is applied is closed, and which
bolt can be unfastened from either side of the door by turning a knob handle
in either direction; and the same sliding bolt is also made to answer the
purpose of a locking bolt, which, by aid of the key inserted from either side of
the door, can be shot farther out from the lock in order to lock the door, and
then the said bolt cannot be withdrawn so as to unlock the door except by aid
of the key.
Figure 1, Sheet I., of the Drawings hereunto annexed represents a door
Jock of the kind called a mortice lock, which is constructed according to my
said improvements. A is the sliding bolt, the end a thereof, which protrudes
out from the lock, being bevilled suitably for acting in the usual manner of
spring bolts against the fixed striking plate when the door is in the act of
closing, so as to push back the bevilled end a of the bolt wholly into the lock
until the door is quite closed, and then the bolt is suddenly shot out again, as
it appears at a in the Figure, by action of its spring B, so as to fasten of itself.
In order to fasten the door on the latch in the usual manner of spring bolts in
ordinary door locks, and in like manner thereto, the said end a of the bolt can

page_text: be wholly withdrawn into the lock in opposition to the spring B, by action of
the follower D, E, on turning the same partly round in either direction about
its centre of motion at d, by application of the hand to one or other of the
knob handles on the ends of the spindle which passes through the square
central hole d of the follower, and there is a knob handle on each end of the
spindle for unfastening the door from either side thereof in the usual manner
of ordinary door locks. The follower D, E, applies laterally against a lever F,
which is moveable about a fixed stud pin 6 as its centre of motion, and has &
pine at the end of it, serving as the centre of motion for the tumbler G,
which, as well as being the tumbler of the lock, also performs the office of a
connecting link between the lever F and the sliding bolt A, for transmitting
to that bolt the action which the spring B exerts behind the lever F, so as to
protrude the end a of the bolt out from the lock, or for transmitting to the
bolt any action which one or other of the ends D or E of the follower may
exert against the lever F, so as to withdraw the said end a of the bolt into
the lock in opposition to the spring B, and for that purpose the projecting
tooth of the tumbler enters into a deep notch cut in the bolt A, and the
action of the tumbler spring H keeps the said tooth i pressed quite into
the said deep notch, when, by application of the hand to either of the knob
bandles, the follower D, E, is turned partly round in either direction about its
centre of motion d, one or other of its ends D or E will act against the lever
F, so as to move the same about its centre of motion b, in opposition to the
spring B, and the centre pine of the tumbler G being at the end of the lever
F, the tumbler G is at the same time moved in the direction of its length,
together with the sliding bolt A, a, (in consequence of the tooth i of the
tumbler being lodged in the deep notch in the bolt,) so as to withdraw the end
a of the bolt within the lock; and when the said knob handle is released, then
the action of the spring B, behind the end e of the lever F, moves the centre
pin e, and the tumbler G, and the bolt A, in a contrary direction, so as to
protrude the end a out from the lock, as it appears in the Figure.
Note. The end E of the follower is shorter from the centre of motion d
than the end D, because the short end E acts against the lever F nearer to the
centre of motion 6 of the lever F than the long end D of the follower acts
against the same lever F. The motion of the lever F is limited by a fixed
stud pin m, against which the lever F rests, when urged to the utmost by the
spring B. The bolt A is guided by a fixed stud pin n, which is received in a
slot cut through the bolt. That part of the tumbler G wherewith the tumbler
spring H comes in contact, is adapted for permitting the said part to slide
freely against the spring H, when the tumbler G moves in the direction of its

page_text: length. The sliding bolt A, when acting in manner aforesaid, answers the
purpose of the spring bolt or latch in ordinary door locks, but the same sliding
bolt A also answers the purpose of a locking bolt when the key is inserted into
the Keyhole K, and turned round in the wards k. The key then coming in
contact with the tumbler at j, lifts the tumbler G or moves the same about its
centre pin e, so as to remove the tooth i of the tumbler out of the deep notch
in the bolt A; but as soon as the tumbler has been so lifted only a very little
way, then the said tooth i begins to apply itself behind a stud pins, which is
fixed into the lock plate in such a position that the fixed studs did not inter-
fere with the tooth i so long as the same remained lodged quite within the
deep notch in the bolt A, and therefore the fixed studs did not then prevent
the aforesaid endway motion of the tumbler G, because the tooth i of the
tumbler passed beneath the fixed stud s; but when the tumbler G is lifted by
the key only a little way, then the aforesaid endway motion of the tumbler is
wholly prevented, in consequence of its tooth i applying itself behind the fixed
stud s, and as soon as the key has lifted the tumbler G so high as to remove
its tooth out of the deep notch in the bolt A, then the key, in turning
further round, enters into the notch w in the bolt A, and begins, with the
usual action of a key on a bolt, to shoot the bolt A endways, so that the end a
will protrude farther out of the lock in order to lock the door; and after the
bolt A, a, has been so shot further out, then the key, quitting the notch w in
the bolt, ceases to give any further motion thereto, but at the same time the
key begins to let down the tumbler G, so that the tooth i thereof enters into
another notch t in the bolt, in order to retain the bolt in its new position;
but the said notch t being only half as deep as the deep notch before men-
tioned, it will not let the tumbler G so low down as that its tooth i can
escape from an effectual contact with the fixed stud s; wherefore, when the
key has quitted contact with the tumbler at j, and the tooth i is lodged in the
notch of the bolt, the said tooth i also bears against the fixed stud s, which
wholly prevents the tumbler G and the bolt A from moving endways so as
to be unlocked except by aid of the key; and on turning the key back-
wards, it first lifts the tumbler G so as to remove its tooth i quite out of the
notch t in the bolt A, and then the key, by acting in the notch w in the bolt,
withdraws or unlocks the bolt A, and then lets the tumbler G down again;
and its tooth i entering into the deep notch in the bolt A, that tooth i descends
low enough to quit all contact with the fixed stud s, and the tooth i will be at
liberty to pass under the fixed studs whenever the bolt is drawn further back,
which may be done by action of the follower D, E, as already explained, or
otherwise may be done by the key, if preferred, because by continuing to turn

page_text: the key round further backwards it comes against the -part x of a notch in the
bolt A, and acts to withdraw the same, with the end a thereof, wholly within
the lock, in like manner as would be done by action of the follower.
The cross bolt N
But, note, the key has no action on the tumbler G when it acts at a on the
bolt A, in manner aforesaid. The sliding bolt A, a, can be retained from
being withdrawn, when required, by means of a small cross bolt N, which
slides in a direction at right angles to the bolt A, and the cross bolt N. termi-
nates with a round pin, which enters into a corresponding hole, shewn by
dotted lines at y in the bolt A. The cross bolt N is lodged in a space left
between a fixed stud plate p and the inside of the lock, and can be moved,
when required, by a small lever M, which has a square hole at its centre of
motion for the reception of the spindle of a small knob handle at that side
of the door which is within the apartment; and by applying the hand to turn
the said knob handle, the round end of the cross bolt N can be shot into the
hole y in the bolt A, so as to detain and wholly prevent the same from being
withdrawn, either by action of the follower or of the key.
can be so shot, either when the bolt A is locked or shot out to its furthest
extent, and will then prevent the lock being unlocked even by the key; or the
cross bolt N can be so shot when the bolt A is only on the latch, as it appears
in Figure 1, there being two holes, such as at y, in the bolt A for the reception
of the end of the cross bolt N; and, if required, there may be a third hole in
the bolt A, suitable for retaining the bolt A when its end a is wholly with-
drawn within the lock. And although Figure 1 is represented as a mortice
lock, the said Figure, together with the foregoing description thereof, will be
sufficient instructions for making a rim lock, or other description of locks, with
similar internal parts. But in case of such a lock being required to be
included within a shorter length, it may be constructed as represented in
Figure 2, wherein the internal parts are similar to those in Figure 1, and are
all marked with the same letters of reference, so as that the foregoing descrip-
tion of Figure 1 will for the most part apply equally to Figure 2. The chief
difference between Figure 2 and Figure 1 is in the circumstance of the lever
F being au elbow lever with two arms, F and F, Figure 2, at right angles
one to the other. The arm F is acted upon by the follower D, E, and the
arm F carries the pin e, which serves as the centre of motion for the tumbler
G. The elbow form of the lever F, F, permits of the follower D, E, being
disposed above the bolt, instead of at the end of the bolt, as in Figure 1, and
therefore the lock, Figure 2, is rendered shorter in length, although it is
higher than in Figure 1. Also, in Figure 2, the same spring B, H, serves the
double purpose of the spring for the bolt A, and the spring for the tumbler G,

page_text: instead of the two separate springs B and H in Figure 1, all which is
sufficiently obvious from inspection of the Drawings. A small cross bolt,
such as N, Figure 1, may be applied in the lock, Figure 2, if desired.
And, note, in case greater security is required in such locks against pick-
locks than can be obtained by the use of the tumbler G, in manner herein-
before described, one or more additional tumbler or tumblers, of any approved
kind, may be introduced into the lock, Figure 1 or Figure 2.
Such an
additional tumbler should have a centre of motion of its own, and should have
no connection with the lever F or F, and such additional tumbler should have
no effect upon the bolt A, to prevent the same from being withdrawn when
the bolt A is in the position shewn in Figures 1 and 2, but when the bolt A is
shot farther out from the lock, or locked as herein-before described, then the
said additional tumbler or tumblers is or are to become operative in con-
currenco with the tumbler G, (but quite independently thereof, and inde-
pendently one of the other, if more than one,) for preventing the bolt A from
being withdrawn, except by aid of the key, all which is well known to lock-
smiths; and space for such additional tumblers may be obtained between the
bolt A and the plate of the lock, and the key must be formed with different
steps, to suit the several tumblers. And in case it is intended that the key
is to be inserted into the lock from either side of the door, then the arrange-
ment of the said steps of the key, as well as of the wards therein, must be
symetracal, according to the usual practice in such case.
Figure 3, Sheet II., represents a mortice lock having all the same properties
as the lock, Figure 1, but with the internal parts differently constructed; the
same letters of reference are used in Figure 8 as in Figure 1 to denote the
same parts where they are alike, or to denote similar parts where there are
differences of form or arrangement. The follower D, E, and the lever F,
with its spring B, are the same as already described in reference to Figure 1,
and so is the small cross bolt N, and its lever M, also the keyhole K, and
the wards k. The sliding bolt A, a, is similar in action, but different in shape.
The fixed stud pin n, and slot in the bolt A for guiding its sliding motion, is
the same as in Figure 1. The tumbler G in Figure 3 is mounted on a
centre pin E, which is fastened into the bolt A; and the spring H of the
tumbler is also fastened to the bolt A, so that the tumbler G, as well as its
spring H, always accompanies the bolt A when the same slides or moves
endways; and the end I of the tumbler acts against a fixed stud pin S
whenever the tumbler is to operate for keeping the bolt locked. C is a stud
pin, fastened into the bolt A, for limiting the descending motion that can be
given to the tumbler G about its centre E by its spring H. It has been

page_text: already stated in the foregoing description of Figure 1, near to the commence-
ment of that description, that the tumbler, as well as being the tumbler of
the lock, also performs the office of a connecting link between the lever F
and the sliding bolt A, a, and the same may be said respecting Figure 3,
for the tumbler G has a projecting tail P at the end beyond its centre of
motion E, and the requisite connection is made by the pin e at the end of the
lever F being received into a notch in the tail end P of the tumbler, and so
long as the pin e is lodged in the said notch (as it is represented to be in
Figure 3), then any motion given to the lever F about its centre pin b, either
by the follower D, E, or by the spring B, will be duly transmitted to the
sliding bolt A, a, in order to move that bolt endways, so as to move the end
a of the bolt A in or out of the lock to the extent shewn at a in Figure 3,
in the same manner as already explained respecting Figure 1; and the end
I of the tumbler G, Figure 3, offers no impediment to that extent of sliding
motion of the bolt A, a, which, when acting in that manner, answers the
purpose of the spring bolt or latch in ordinary door locks; but the same
sliding bolt A also answers the purpose of a locking bolt when the key is
inserted into the keyhole K, and turned round in the wards k; the key then
coming in contact with the tumbler at j, lifts the tumbler or moves it about
its centre of motion E, so as to remove the beak I at the end of the tumbler
from its previous contact with the fixed stud pin S; and by the same motion
of the tumbler its tail end P descends so much as that the notch in the end
of P will clear itself from the pin e at the end of the lever F, in order to
entirely disconnect the said lever F from the bolt A, and then the key, in
turning further round, enters into the notch w (dotted) in the bolt A, and
begins with the usual action of a key on a bolt to shoot the bolt A end ways,
so that the end a will protrude further out of the lock than is represented,
in order to lock the door, the tumbler moving with the bolt when it is so
shot further out, and then the key quitting the said notch w ceases to give
any further motion to the bolt A, but at the same moment the key begins to
let down the tumbler G, so that by the time the key has passed away from
the tumbler, and has quitted contact therewith at j, the beak I at the end
of the tumbler will become hooked over the fixed stud pin S, in order to
prevent the bolt A being withdrawn or unlocked except by application of
the key.
And, note, although the letting down of the end I of the tumbler causes
the tail end P to rise up, nevertheless, the notch in P does not in consequence
become reengaged with the pin e of the lever F, because the endway motion
of the tumbler along with the bolt A has carried the end of P away from

page_text: the pin e; and when the key is reinserted and turned round backwards, it
first lifts up the tumbler G, by acting beneath the same at j, so that its beak
I is removed from its contact with the fixed stud pin S, in order to set the
bolt A at liberty, and then the key acting in the notch w (dotted) in the bolt
A, withdraws and unlocks the bolt A, the tumbler G moving with the bolt,
and immediately after that the key begins to let down the tumbler G, and
the tail end P thereof rising at the same time, its notch becomes reengaged
with the pin e of the lever F, in the manner represented in Figure 3.
Note. Figure 4 represents a similar lock, but with the bolt A, a, in an in-
termediate position between being locked and being unlocked, and that Figure
will serve to explain how the notch in the tail end P of the tumbler G
becomes disengaged from the pin e of the lever F, or reengaged therewith,
as above described. The lock, Figure 4, differs from Figure 3 in the tumblers
G,g, whereof, for greater security, there are two, G and g, both being mounted
on the same centre pin E, which is fastened into the bolt A, and the tail end P
of one of those tumblers G, which is seen in Figure 4, is the same as in
Figure 3, but the other tumbler g, of which only part can be seen, does not
extend beyond the centre E, and has no such tail end. The ends I of the
two tumblers G and 9 act against the fixed stud pin S, and there are notches
cut out in the ends I of the tumblers, as shewn in the Figure, for the recep-
tion of the said fixed stud pin S. The tumblers G, g, are lifted by means of
two intermediate levers J, one for each tumbler, both which levers are move-
able about one fixed centre pin r, and the extremities of the levers Japply to
the tumblers atj. The key, when turned round acts beneath the two levers J,
near to the middle part of their length, so as to lift them up, and then by
acting at j beneath the two tumblers, lift up each of the tumblers just as
much as is suitable for that tumbler, so as that the notch at the end I of both
tumblers will be brought to an exact correspondence with the fixed stud pin S,
and then (but not before) the key begins to act in the notch w of the bolt A,
so as to shoot or slide the same endways, and the tumblers G, g, moving with
the bolt A, their notches will pass over the fixed stud pin S, in the manner
represented in Figure 4. Also, in so moving the part j of the two tumblers
slide along over the ends of the two intermediate levers J, and by the time the
key has shot the bolt A to its full extent, it will have quitted contact in the
notch w of the bolt, and will also have quitted contact with the levers J, and
therefore the tumblers G, g, will be successively pushed downwards by action
of their springs H, so as to hook over the fixed stud pin S, which thereby
becomes included within the interior of the notches in the ends I of the
tumblers. There are two springs H, one acting on each tumbler G and g.

page_text: The said two two tumblers G, g, are of the nature of the tumblers which are
used in locks for which Mr. Barron formerly had a Patent, and which are
still known by the name of Barron's tumblers b, inasmuch as that the said
tumblers G, g, will not allow the bolt to be moved if either tumbler G or g is
lifted any higher up than the proper place, or if either tumbler G or g is not
lifted up just as high as that proper place; so that the action of the key
beneath the levers ; must lift both tumblers exactly to the proper height,
without lifting either of them too high, or else the bolt cannot be withdrawn,
thus giving security against unlocking the lock by picklocks or by false keys,
all which is well known to locksmiths. And the lock, Figure 4, is the same
as Figure 3 in every other respect, except the duplication of the tumblers G, g,
and the adaptation of those tumblers to operate in the manner of Barron's
tumblers, as aforesaid.
And, note, the intermediate levers J are not absolutely necessary, as the key
might be made to act beneath the tumblers G, g, provided they were formed
with proper prominences at the part j of each tumbler. A small cross bolt,
such as N, Figures 1 and 3, may be applied in the lock, Figure 4.
Figure 5, Sheet III., represents a latch-lock, which is the same in every
respect as Figure 3, except that no key is required to be used, and then it is
termed a latch instead of a lock or a latch-lock. In place of the keyhole K
and wards k in Figure 3, a turning lever K is applied in Figure 5, with a
square central hole for the reception of the square spindle of a knob handle,
which is to be at that side of the door which is within the apartment, and by
turning that knob handle in the same manner as the key would be turned in
the lock, Figure 3, the same effects of shooting the bolt A, Figure 5, will be
produced, as already explained in reference to Figure 3.
And, note, in all the locks, Figures 1, 2, 3, 4, and also in the latch-lock,
Figure 5, when the sliding bolt A, is unlocked and on the latch, as is
represented in those Figures (except in Figure 4), then the key or knob
handle in Figure 5, (being turned backwards, will withdraw the bolt A, so that
its protruding end a will be withdrawn within the lock, in the same manner
as already explained in respect to Figure 1.
And as to my improvements on spindles and knobs for locks and latches,
the same consist in certain means, herein-after particularly described, whereby
the spindles and knobs for door locks and latches are so constructed that they
will adjust themselves to suit the thicknesses of the doors to which the locks or
latches may be applied, without requiring any alteration of the spindles to
suit doors of different thicknesses, and the knobs are firmly secured to the
wood of the door on one or both sides thereof, so as not to be liable to come

page_text: off or work loose, as is the case in the ordinary way of affixing the knobs
to the ends of the spindle, and depending solely on the spindle for sustaining
the knobs.
Spindles and knobs constructed according to my improvements are repre-
sented in Sheet III., wherein Figure 6 is a section of a metal knob V, hollow
within, and having a square hole f within the shank part g, g, of the knob, for
the reception of the spindle T, which is a square spindle of iron, shewn sepa-
rately at Figure 8. Instead of the rose, or small flat circular collet of metal
which is usually applied around the spindle against the wood of the door, and
fastened thereto with small pins, the collet or rose, according to my improve-
ments, is a substantial circular plate or disc of metal W, W, Figure 6, and
shewn separately in Figure 7, the circumference of which is applied against
the wood of the door, and fastened very securely thereto by three or more
screws of the kind called wood screws, the said collet W being concave at the
side which is so applied against the wood. The central hole through the
collet W, Figure 6, receives a circular neck at the end of the shank part g, g,
of the knob V, with a projecting shoulder h, h, around that neck, which
shoulder applies to a margin around the central hole of the collet W at the
outside thereof, and the neck protrudes a little way through the said central
hole of the collet W to the inside or cavity thereof, and a small ring, u, u, of
metal is securely rivetted or soldered (or otherwise fastened) on that part of
the neck which protrudes through the central hole, wherefore the said ring
u, u, applies against a margin around the central hole of the collet W at the
inside thereof, the ring u, u, being within the concavity of the collet W, and
the end of the neck of the shank g, whereon that ring is fastened, being also
within the collet W, so as not to touch the wood of the door when the collet
W is applied and fastened thereto, as aforesaid. By these means the shank
part g of the knob is truly fitted and secured to the collet W, (but so as to be
capable of turning round freely in the central hole thereof,) and when the
collet W is fastened to the wood of the door, the knob is firmly sustained at
its proper place on the door by its aforesaid connection with that collet without
much dependance upon the spindle T, the middle part of which is inserted
into the square central hole through the follower, (see d, Figure 1,) and the
end of the spindle T enters and fits truly into the square hole f within the
shank part 9 of the knob, but it is not fastened therein. Figure 9 is a
horizontal plan, which explains the manner of applying two knobs and a
spindle, constructed according to my improvements, to a door having a mortice
lock inserted into the thickness of the wood of the door. 1, 1, represents that
mortice lock, the exterior elge of which is shewn, except a portion near to the

page_text: spindle and knobs, which is shewn in section, in order to shew the follower
D, E, within the lock. a is the bolt of the lock 3, the front plate thereof;
and 4, 4, part of the wood of the door. T is the square spindle, (see also
Figure 8,) the middle part of which passes through and fits truly into the
square central hole of the follower D, E, but is not fastened therein. The two
ends of the spindle T project out each way, in order to enter into the square
holes (see f, Figure 6) within the shank parts of the knobs 5 and 6 at each
side of the door; but the ends of the spindle, although they fit truly into the
said square holes f, are not fastened therein. The knob 5 is shewn externally,
and the knob 6 in section. They are represented as wooden knobs, but they
have metal, z, z, within their shanks, (as will be further explained,) and those
metal parts have the aforesaid square holes within them which receive the
ends of the spindle T, and also those metal parts are fitted to and turn round
within the central holes of the collets W, W, which are applied against each
side of the door, and are fastened thereto by screws, as already explained, and
by that means the knobs 5 and 6 are sustained firmly in their places, and
prevented from coming off; the two ends of the spindle T, entering into the
interior of the knobs, assist in keeping them firmly in place, but cannot assist
in preventing the knobs coming off, because the spindle T is not fastened to
any part, but it is merely inserted with its middle part through the square
central hole in the follower D, E, and with its two ends inserted into the
square holes within the shank parts of the two knobs. The length of the
spindle T (see also Figure 8) is such as that its ends will reach quite through
the aforesaid square holes (f, Figure 6) within the shank parts of the two
knobs 5 and 6, Figure 9, in cases when the wood, 4, 4, of the door is of the
greatest thickness that is usual in doors of apartments; but in case of that
wood being thinner then the ends of the spindle T, can pass through beyond
the said square holes within the shank parts of the knobs, and the said ends
will be received into the hollows of those knobs without requiring the length
of the spindle to be altered to suit the thickness of the door.
Figure 10 is a horizontal plan similar to Figure 9, but shewing the manner
of applying a spindle and a knob, constructed according to my improvements,
to a door having a rim lock, 1, fastened by screws against the inside of the
door. The same letters and numerals being used as in Figure 9 to denote
the same parts, a brief explanation will suffice. The knob 5 in Figure 10 is
firmly fastened on one end of the square spindle T by a cross pin (or other-
wise), and the spindle T is inserted through the square central hole of the
follower D, E, within the lock, and the spindle T is retained from drawing out
through the follower by a small screw 7, which is inserted crossways into the

page_text: spindle at the part where it comes out through the follower D, E, at that side
of the lock which is to apply against the wood of the door.
The screw 7 bears against the end of the follower D, E, and retains the
spindle T securely therein. The middle part of the spindle T passes through
a round hole through the wood 4, 4, of the door, and the other end enters
into the square hole within the shank part g, g, of the knob 6, which is applied
and sustained in its place at the outside of the door by means of its collet W,
in the same manner as already explained in reference to Figure 9, and with the
same result, viz, that difference in the thickness of the wood 4, 4, of the door
is allowed for without requiring any alteration of the length of the spindle T.
In Figure 9, the adjustment for difference of thickness of the door is made at
both knobs 5 and 6, and at each end of the spindle T; but in Figure 10, the
said adjustment is only made at one of the knobs 6, and at one end of the
spindle T.
Note. The knob 6 in Figure 10 is represented to be a metal knob
of the same construction as Figure 6 already explained; but the knob 6 in
Figure 9 is represented to be a wooden knob, and it has a piece of metal z.
fastened by screwing, cementing, cross pinning, or otherwise firmly fastened
within the shank part of the wood knob 6, and the square hole for the
reception of the end of the spindle T is made through the said piece of metal <,
which is fitted truly into the central hole through the collet W, so as to turn
round freely in that hole, in manner and for the purpose already explained in
reference to Figure 6, except that the piece of metal z, Figure 9, is formed
with its projecting shoulder h, h, at the extreme end of it, in order to apply
within the concavity of the collet W, and the ring or washer u, u, is applied
on a screw thread cut around the exterior of the piece z at the part where
the piece comes through the central hole of the collet W. The ring or
washer u, u, being screwed on the outside of the piece until it retains the
same in its intended connection with the collet W, and then the wood knob 6
is screwed very stiffly on the said screw thread around the outside of z with
the aid of cement to prevent unscrewing (or a cross pin may be inserted to
assist the cement), so as to unite the wood knob firmly to the piece of metal =
in the manner shewn in the section, Figure 9. The square spindle T may be
constructed in any of the three different ways shewn in Figure 8 at T, 7',
and Z. T is merely a straight square bar of iron of the same size from end
to end. The square holes through the centre of the follower, and within the
shank parts of the knobs, being exactly of the same size, and adapted to
receive the square spindle without sensible looseness. T, Figure 8, is a
similar square spindle formed like a fork with two prongs, which act in the

page_text: manner of a spring, so that the spindle will expand when it is inserted in
place, in order that it may retain itself within the said square holes wherein
it is inserted without looseness therein. Z, Figure 8, is a square spindle
formed of two tapering or wedge-like pieces of iron applied side by side with
the thick end of one piece opposite to the thin end of the other piece, in the
manner of folding wedges, as is apparent in the Drawing. When the spindle Z
is inserted in its place with the middle part of its length through the central
hole of the follower D, E, of the lock, then one of the two wedge-like pieces
of which the spindle Z is composed is to be thrust endways in the proper
direction to advance its thin end foremost without allowing the other piece to
move endways with it, and thereby the wedge-like form of the two pieces will
cause the spindle Z to expand itself so as to fill the square hole into which it
is inserted without having any looseness therein. Figures 11, 12, 13, and 14
are sections of knobs of different kinds having the same properties as Figure 6,
already described, videlicet, that the knob V is firmly connected with the
collet W, which is fastened against the door by screws, the connection being
such as that the knobs V can turn round freely in the collet W, but cannot
be separated therefrom, nor displaced from its proper position on the door, nor
removed from the door, unless the collet W is detached from the wood thereof.
Figure 11 is a wooden knob V having a piece of metal z inserted and fastened
therein, which piece has a square hole through it for the reception of the
end of the spindle T, and the piece is formed with a neck at the end of it,
and a projecting shoulder h, h, around that neck, which neck and shoulder
are fitted to the central hole of the collet W, and are retained therein by a
ring of metal u, u, rivetted or soldered on the said neck, in the same manner
as already explained in reference to Figure 6. The piece z, Figure 11, being
very like to the shank part g, g, of the knob, Figure 6, except as to the
exterior of z, Figure 11, being cut with a screw thread around it, in order to
screw stiffly (with cement) into the wood V of the knob, so as to fasten the
piece very securely to that wood V, as already explained respecting the
knob 6 in Figure 9. Figure 12 is a similar plan to Figure 11, except that
the piece of metal = (instead of a screw thread) has only grooves formed
around it to give better hold to the cement by which it is to be fastened into
the knob V, which knob may be made of glass, porcelain, horn, wood, ivory,
paper, or any other suitable substance of which such knobs are or can be
made, and the same of Figures 13 and 14, wherein the piece of metal z is
to be fastened into the knob V by cementing (but cross pinning may in some
cases be added for security), and the piece of metal z may be six or eight
sided on its exterior, in order to give more secure hold in the knob V by the

page_text: cementing. The piece of metal z is represented in Figures 13 and 14 with
a projecting shoulder around the extreme end of it to go within the concavity
of the collet W, in the same manner as already explained in reference to the
knob 6, Figure 9, except that there is no ring or washer such as u, u, in
Figures 13 and 14, but the end of the shank part of the knob V comes in
contact with the outside of the collet W, around the margin of the central
hole thereof. X, X, Figure 14, shews, in section, how an ornamental shield
or covering ring may be applied over the collet W, in order to conceal the
same, together with the screws by which it is fastened to the wood of the door,
if desired. The shield X, X, being fastened to the collet W by ornamental
studs.
And, note, spindles and knobs constructed according to my improvements, as
herein-before described, may be applied to doors which have been heretofore
fitted with knobs and spindles of the common kind, retaining the same locks, if
they are of good construction and in good condition, or applying new followers
to such locks, if requisite, in order that they may fit truly to the new spindles.
Having now described my said improvements, I, the said Benjamin Pitt, do
hereby declare that what I claim as the new Invention, whereof the exclusive
use is granted to me by the Letters Patent herein-before recited, consists the
following particulars, videlicet,-
Firstly, the improvements in locks and latches, herein-before described in
reference to Figures 1, 2, 3, and 4, whereby the tumbler of the lock, (or one of
the tumblers of the lock, in case of more than one being used therein,) is
caused to act in the manner herein-before described as a connecting link, by
means whereof the sliding bolt A, a, of the lock cau be withdrawn when
the same is on the latch, so as to withdraw its bevilled end a wholly within the
lock by the usual action of the follower D, E, which action results from turning
the knob handle (at either side of the door) either way round; but which
tumbler aforesaid operates (in the usual and proper manner of a tumbler),
when the sliding bolt is locked (by action of the key), for retaining the bolt
from being withdrawn or unlocked unless by aid of the key, and by those
means the same sliding bolt in the lock is made to answer the double purpose
of a spring bolt or latch, which will fasten of itself on closing the door, and
which can be withdrawn in order to open the door by turning a knob handle
at either side of the door in either direction; and also the said sliding bolt
is made to answer the purpose of a locking bolt, which, by aid of the key
inserted at either side of the door, can be shot farther out from the lock
in order to lock the door, but which bolt cannot be withdrawn so as to unlock
the lock except by aid of the key.

page_text: But, note, whereas some locks have been heretofore invented having the
property of causing one sliding bolt to answer the double purpose aforesaid, I
confine my claim to the improved construction of locks, herein-before described
in reference to Figures 1, 2, 3, and 4, whereby that said property is attained.
Secondly, the improvement in latches or latch-locks, herein-before described
in reference to Figure 5, which is very similar to Figures 1, 2, 3, and 4, except
that no key is required to be used
Thirdly, the improvement in spindles and knobs, herein-before described in
reference to Figures 6 to 14, whereby the spindle is not fastened to the knobs,
(or only to one of the knobs, as herein-before explained in reference to Figure
10,) the said knobs (or one of them) being connected with a collet or rose,
such as W, which is securely fastened to the wood of the door, in the manner
herein-before explained, so as, by the mode of connecting, to allow the knob
to turn freely round, but so as to sustain the knob firmly in its intended
place on the door (and prevent the knob coming off), without the knob being
fastened to the spindle, which in consequence will adjust itself, as herein-
before explained, to doors of different thicknesses without alteration of the the
length of the spindle.
In witness whereof, I, the said Benjamin Pitt, have hereunto set my
hand and seal, this Fourteenth day of November, in the year of our
Lord One thousand eight hundred and forty-four
BENJAMIN (L.S.) PITT.
AND BE IT REMEMBERED, that on the Fourteenth day of November,
in the year of our Lord 1844, the aforesaid Benjamin Pitt 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 accord-
ing to the tenor of the Statute made for that purpose.