IMPROVEMENTS IN LOCKS
Year: 1881

page_text: LETTERS PATENT to George Hayter Chubb of No. 128 Queen Victoria Street
in the City of London and Harry Withers Chubb of Summerhill Villas
Chislehurst in the County of Kent for an Invention of "IMPROVEMENTS IN
LOCKS"
PROVISIONAL SPECIFICATION left by the said George Hayter Chubb and
Harry Withers Chubb at the Office of the Commissioners of Patents on the
10th December 1881.
GEORGE HAYTER CHUBB of No. 128 Queen Victoria Street in the City of
London and HARRY WITHERS CHUBB of Summerhill Villas Chislehurst in the
County of Kent. " IMPROVEMENTS IN LOCKS."
This Invention has for its object improvements in locks.
In order to keep the bolts of locks for safes and other such like locks locked out
in the event of the interior or any part of the interior of the lock being destroyed
by gun-powder acids picks drills or other means we form in the lock case on either
side of the bolt-head two chambers or recesses with strong stout surrounding
walls, such recesses having but one opening into them and that being closed by
the side of the head of the bolt fitting closely up to it. In each recess we place a
V or feather spring one end of each spring bears against the back of the recess
the other carries a roller that rests against the side of the bolt and revolves as the
bolt is moved in or out by the lock key. The sides of the bolt head are flat and
parallel except at a point just where the rollers remain when the bolt head is out
and here the sides of the bolt head commence to curve inwards in such a form
that if the bolt head were not held in its place by the tumblers and stump of the
lock, the pressure of the springs acting on the rollers would force the bolt out
further and hold it fast in that position. In case therefore the tumblers, stump,
bolt tail or other parts of the lock are destroyed the bolt becomes fastened and
cannot be moved without getting the rollers away from the cavities in the sides of
the bolthead.
Padlocks we form in such a manner that the hinged shackle or hasp instead of
being locked by a bolt shot forward into its end as in ordinary padlocks is for the

page_text: greater part of its length made to form part of the side of the lock case and is
locked and held by a projection from its inner side being caught by a series of
tumblers which have to be set in position by the key before the shackle or hasp
can be released and the lock opened. The padlock may be of any suitable form
but by preference we make it so that the outer circumference of the case together
with the shackle or hasp is circular. At one point of the circumference of the case
we make a convenient opening to receive a staple. To the opposite side of the
circumference of the case we joint the shackle or hasp either by a stump or by its
end being held in a circular cavity formed in the lock case or by both combined.
When the lock is closed the extremity of the shackle or hasp passes across the
mouth of the radial opening. Each tumbler at its end is made with an anchor
shaped or T head or of any other suitable form. The shackle or hasp midway of
its length has projecting inwards from it two hook shaped projections at a distance
apart from one another-the heads of the tumblers pass between these hook
projections and when the lock is closed one of the projecting arms of the T head
of each tumbler hooks over one of the hook projections and retains the shackle or
hasp in its locked position. If in any attempt to pick the lock any of the tumblers
are turned round to a greater extent that is just requisite to free them from this
hook projection they catch over the other hook projection and so again lock the
shackle or hasp. The abutting surfaces of the tumblers and hook projections on
the shackle or hasp are preferably-notched-to-give-greater_security.When the
tumblers are set by the proper key into such a position that they no longer catch
over either of the hook projections the shackle or hasp is free and can be turned
on its joint a distance just sufficient to leave open the entrance into the radial
opening of the case. The padlock can then be removed from whatever fastening
it was previously being used to secure.
The key hole of the lock is preferably in a line with the radial opening
in the lock case on the opposite side of the centre of the lock case and the
tumblers are made with crank arms for the key to act against they thus form
what are known as "balance tumblers." The tumblers besides being balanced on
the centre pin or stump of the lock have circular bosses at their centre which work
in a round cavity cast with the lock plate-or the tumblers may be used without
the centre pin or stump, merely being kept in their places by and working in the
cavity.
If the tumblers are made to be what are known as flush bellied tumblers the
shackle or hasp where it is held by the tumbler may be shaped as a counterpart of
the steps of the key. The tumblers themselves might also be of other shape than
that described.
The shackle or hasp in place of being in one piece as above described may be.
made of several plates of metal moving independently of one another and each
locked by a separate tumbler.
The plate and rim are cast in one, the cap being rivetted screwed or fastened on.
A barrel and curtain with flat keys are also used.
Within the space or recess in the shackle or hasp left between the two hook
projections above mentioned may be fitted a loose lining guard of such a shape
that if any or all of the tumblers be over lifted that is turned too far round it will
aid in keeping the shackle or hasp in its locked position.
This method of securing the main bolt by direct engagement with the tumblers
may be applied to locks of other descriptions than padlocks.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said George Hayter Chubb and Harry Withers Chubb in the Great
Seal Patent Office on the 10th June 1882.
GEORGE HAYTER CHUBB of No. 128 Queen Victoria Street in the City of
London and HARRY WITHERS CHUBB of Summerhill Villas, Chislehurst in the
County of Kent. IMPROVEMENTS IN LOCKS."
This Invention has for its object improvements in locks.
In order to keep the bolts of locks for safes and other such like locks locked out
in the event of the interior or any part of the interior of the lock being destroyed
by gunpowder acids picks drills or other means, we form in the lock case on either
side of the bolt head two chambers or recesses with strong stout surrounding
walls such recesses having but one opening into them and that being closed by the
side of the head of the bolt fitting closely up to it. In each recess we place a V or
feather spring-one end of each spring bears against the back of the recess the
other carries a roller that rests against the side of the bolt and revolves as the
bolt is moved in or out by the lock key. The sides of the bolt head are flat and
parallel except at a point just where the rollers reinain when the bolt head is out
and here the sides of the bolt head commence to curve inwards in such a form that
if the bolt head were not held in its place by the tumblers and stump of the
lock, the pressure of the springs acting on the rollers would force the bolt out
further and hold it fast in that position. In case therefore the tumblers stump,
bolt tail or other parts of the locks are destroyed the bolt becomes fastened and
cannot be moved without getting the rollers away from the cavities in the sides of
the bolt head.
Figure 1 of the Drawings hereunto annexed shews a section of a lock constructed
as above described. Figure 2 is an end view of the same with the cover plate
removed Figure 3 is a plan of the inside of the cover plate Figure 4 shews how
the bolt is held in the event of the interior of the lock being destroyed.
A is the foundation plate of the lock case. B is the bolt. C the cover plate.
A¹, A¹ are stout projections standing up from the plate A. They each form a stout
wall enclosing a chamber in which is contained a V spring D one limb of which
carries a roller D' which rests against the side of the bolt. B' B' are two semi
circular recesses in the two opposite sides of the bolt. When the parts of the lock
are intact the bolt when shot comes into the position shewn in Figure 1 and the
rollers D' do not enter the recesses B¹ the further shooting forward of the bolt is
restrained by a small projection B2, from the stump of the bolt coming against the
front end of a slot in one of the tumblers marked E which is longer than the
other tumblers. If however the interior of the lock were to be so far destroyed
that the tumbler E no longer held back the bolt, the spring D would press the
bolt forwards the rollers D¹ then entering the recesses B' and forming obstructions
to prevent the drawing back of the bolt.
It will be seen that the springs D are securely protected from the action of any
acid which may be introduced into the interior of the lock through the key hole-
as they are shut off from the other parts of the interior of the lock by the stout
walls A¹ and by a similarly stout projection C¹ on the cover plate-the projection C¹,
fitting closely to the two walls A₁ and filling up so much of the space between
them as is not occupied by the bolt head.
Padlocks we form in such a manner that the hinged shackle or hasp instead of
being locked by a bolt shot forward into its end as in ordinary padlocks is for the
greater part of its length made to form part of the side of the lock case and is

page_text: locked and held by a projection from its inner side being caught by a series of
tumblers which have to be set in position by the key before the shackle or hasp
can be released and the lock opened. The padlock may be of any suitable form
but by preference we make it so that the outer circumference of the case together
with the shackle or hasp is circular. At one point of the circumference of the
case we make a convenient opening to receive a staple. To the opposite side of
the circumference of the case we joint the shackle or hasp either by a stump or by
its end being held in a circular cavity formed in the lock case
combined. When the lock is closed the extremity of the shackle or hasp passes
across the mouth of the opening and the projection from its inner side is caught by
the tumblers.
or by both
When the tumblers are set by the proper key into such a position that they no
longer catch over this projection the shackle or hasp is free and can be turned on
its joint a distance just sufficient to leave open the entrance into the opening of
the case. The padlock can then be removed from whatever fastening it was
previously being used to secure.
The key.hole of the lock is preferably in a line with the opening in the lock
case on the opposite side of the centre of the lock case and the tumblers are made
with crank arms for the key to act against-they thus form what are known as
"balance tumblers." The tumblers besides being balanced on the centre pin or
stump of the lock-have-circular-bosses-at-their-centre-which-work_in_a_round_
cavity cast with the lock plate or the tumblers may be used without the centre
pin or stump merely being kept in their places by and working in the cavity.
If the tumblers are made to be what are known as flush bellied tumblers the
shackle or hasp where it is held by the tumbler may be shaped as a counterpart
of the steps of the key. The tumblers themselves might also be of other shape
than that described.
The shackle or hasp in place of being in one piece as above described may be
made of several plates of metal moving independently of one another and each
locked by a separate tumbler.
The plate and rim are cast in one, the cap being rivetted, screwed or
fastened on.
A barrel and curtain with flat keys are used by preference as the Drawings
show.
Figure 5 is a plan view with the cover plate removed of a padlock constructed
as above described. In this view the padlock is shewn to be locked. Figure 6 is
a similar view of the padlock when unlocked. Figures 7 and 8 are plan and edge
views of the exterior of the lock when locked. Figures 9 and 10 shew separate
views of the hasp or shackle. Figure 10 being a cross section through the line a, b,
Figure 9. Figure 11 is a plan view of the plate and rim forming the case of the
lock. Figure 12, is a plan view of the inside of the cover plate.
In these views A is the lock plate with rim A¹ cast in one piece with it. On
the inner side of the plate are slightly projecting surfaces A* see Figure 11 upon
which the moveable parts of the lock rest and which alone have to be made smooth
whilst the remainder of the surface of the plate A may be left in its roughened
state as cast. The cover plate B is similarly formed with slightly projecting
surfaces B! on its inner side which alone require to be made smooth.
AB will be seen by the Drawings the lock case is for the most part of a circular
disc form with an opening extending from one portion of the circumference of the
disc towards its centre and the end of the hasp or shackle lies across the entrance
to this opening when the padlock is locked. C is the hasp or shackle with a loop
shaped projection C¹ standing inwards from it. The hasp or shackle is of a
thickness to occupy the space between the plate A and cover B and it closes in so
much of the space between these plates as is not closed in by the rim A¹. It is
shewn as turning on a pin C but the exterior of its end might in addition be
made circular as shewn and be received into a circular recess formed in a lump
standing up from the plate A. D, D are the tumblers turning on a pin E and engaging

page_text: with the loop projection C of the hoop or shackle when the lock is closed. The
tumblers need not necessarily be of the form shewn they might be made T shaped
at their ends and the hasp or shackle be made with two hook shaped projections
standing inwards from it to come one on either side of the ends of the tumblers.
F is a disc curtain with barrel projecting inwards from it-the barrel is slotted
with a narrow slot so that a flat key such as shewn at Figures 13 may be used.
Having thus described the nature of our Invention and the manner of
performing the same we would have it understood that we claim :-
First. The construction of locks substantially as herein before described with
reference to Figures 1 to 4 so as to prevent the bolt being withdrawn in the event
of the interior of the lock being destroyed or partially destroyed.
Second. The construction of padlocks substantially as herein before described
with reference to Figures 5 to 12.
Third. The locking of the hinged hasps or shackles of padlocks by tumblers
engaging with a projection standing inwards from them substantially as herein
before described.
In witness whereof I the said George Hayter Chubb have hereunto set
my hand and seal this Ninth day of June in the year of our Lord One
thousand eight hundred and eighty two.
GEORGE H. CHUBB. (L.S.)