IMPROVEMENTS IN COMBINATION LOCKS
Year: 1877

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN
COMBINATION LOCKS." A communication from abroad by Alfred Edward
Peters, of Moncton, County of Westmoreland, Province of New Brunswick, and
Dominion of Canada.
Sealed the 11th January 1878, and dated the 18th September 1877.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 18th September 1877.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN COMBINATION LOCKS." [A com-
munication from abroad by Alfred Edward Peters, of Moncton, County of West-
moreland, Province of New Brunswick, and Dominion of Canada.]
The object of this Invention is to furnish for doors, drawers, trunks, safes, post-
office boxes, and other purposes, an improved combination lock that may be set
with great facility without giving an opportunity to be picked, as the interior
parts cannot be touched by tools, and which is of greater simplicity of construc-
tion than the combination locks at present in general use, so that by its cheaper
manufacture it may be applied to a number of domestic purposes for which the
former locks are too expensive.
The Invention consists of a spring-acted roller or cylinder with interchangeable pins
that are acted upon by spring bars or fingers depressed by sliding set pins entering
through perforations of the face plate. The set springs are returned by auxiliary
springs, and retained in position, so that only one set pin may be depressed at the time
by sectional guard plates that bind around the pins. The spring fingers are engaged
by a laterally sliding and toothed locking bar that releases the preceding spring as
soon as any one of the remaining springs is depressed, securing thereby the
return of the roller, except when the correct combination of set pins is depressed in
regular succession, which prevents the return of the roller, and allows finally, by
means of a cam at the end of the same, the throwing of the bolt.
.
A

page_text: According to this Invention, the casing of the lock is preferably provided at
the face part, with a raised part having a series of perforations that are numbered or
lettered, and which serve either to guide a corresponding number of projecting
set pins having enlarged and conical inner heads, with smaller end pins, or to
admit the insertion of a key pin of suitable thickness to set the combination thereby.
Behind the perforations are applied to the inner side of the face plate a series of
spring bars or fingers, which correspond in number with the holes, and are fastened
at one end and free at the other, so that by depressing a set pin, or inserting the
key pin, the corresponding spring finger is depressed. A number of sectional guard
plates embrace the conical ends of the set pins, and slide in a guide recess of the
raised part at the outer side of the casing, serving for the purpose of allowing only
one of the set pins to be depressed at one time, as thereby the remaining guard plates
are forced sufficiently apart in opposite directions by the contact of the guard plates,
so that the set pin may enter and depress the spring finger. When more than one
of the set pins are pressed upon, the guard plates cannot give way and lock thereby
the pins rigidly in position, barring their entrance into the lock. This forms an
essential feature in the successful working of the lock, as it compels the depressing
of the set pins and spring fingers successively one after the other.
A toothed and recessed bar is placed below the entrance holes, and at right angles
and transversely to the spring fingers, so that the latter may enter into the cor-
responding teeth when depressed, and be retained by a recess at the base of each
tooth..
A second recess near the tapering head of the tooth forms a kind of safety recess
to produce a click by the spring, and mislead the ear when anyone is trying to
tamper with the lock by attempting to get a clue to the combination by the sense
of hearing.
The toothed locking bar of the fingers slides in supports, and is acted upon by a
spring that carries the bar by the depression of a spring finger sidewise, till the
same has passed into the base recess of the tooth, where it is locked by the bar,
releasing at the same time any spring bar that has before been locked in the same
manner, so that only one spring at one and the same time may be retained thereby.
Between the spring bars and casing are interposed shorter auxiliary springs that
return the set pins to the normal position in the raised part of the casing as soon as
the spring bar is locked by the locking bar.
At the end of the spring fingers and parallel to the locking bar is arranged a
roller or cylinder that turns in the same supports as the locking bar, and is acted
upon axially by a spiral spring. The roller is provided with a number of socket
holes that are bored in the circumference of the roller in line with the centres of
the spring bars. Into these holes may be, interchangeably screwed or otherwise,
applied short pins, of which as many are used as there are set pins and spring bars.
These pins may be set into any desired combination that is possible between the
number of holes employed, a very large number of different combinations being
thus admissable. A fixed pin that is placed in line with one of the longitudinal row
of pin holes, but between two adjoining spring bars, so as not to be engaged by the
same, is thrown by the spiral spring of the roller against a stop of the casing.
The combination by which the pins of the rollers are set has to proceed from the
line of holes in which the stop pin is arranged. When, for instance, the lock is
made with five set pins, and a corresponding number of spring bars and locking
teeth, five longitudinal lines of pin holes, have to be arranged on the roller.
more set pins are used, a larger number of lines of holes has to be arranged on the
roller, the pins being secured into the holes, according to the combination of figures
selected, and in consecutive order in the longitudinal rows of holes, starting from
that in line with the top pin, one pin only however being set into each row of holes.
The roller has a cam at its opposite end that engages a spring-acted plate of the
bolt whenever the roller is brought by the successive depressions of the spring bars
engaging the pins of the roller into the required position, the cam lifting finally
then said plate, and allowing it to slide over a stop plate of the casing, or throwing
When

page_text: the bolt back by a crank pin provided with an outer button. Only by the raising
of the spring plate of the bolt by the cam, may the bolt be thrown back and the lock
opened, this being prevented in any other position of the roller. When therefore the
set pins are depressed, or the key pin inserted in regular succession according to the
combination that has been selected, the spring bars are depressed, striking in this
case one pin after another on the roller, and retaining the roller in position, by the
consecutive contact of spring bars and pins, until the saine is fully turned, and admits
by the action of its cam end the throwing back of the bolt. If however any other
spring bar be depressed, or the regular succession of set pins not kept up, the
preceding spring bar is released, and the roller instantly carried back to its original
position against the stop; or the roller is not affected at all, as no pin is in the way
of the depressed spring bar. Whatever spring may be depressed, the roller cannot
be turned so as to open the bolt without the use of the combination selected.
The lock may be set to a different combination by removing the back plate and
changing the pins in the rollers accordingly.
When it is desired to set the lock to a combination of less figures than there are
spring bars, the stop pin has to be set into a hole further from the original row, and
closer to the cam.
For closing the lock the bolt is thrown, and any one of the set pins depressed, so
that the last retaining spring bar is released, and the roller carried back into its
original position for locking the bolt. This construction furnishes a combination
lock of small and neat shape that may be conveniently used for various applications,
offering the advantage of requiring no key, preventing the tampering with the lock
by tools in effective manner, as there are no exterior openings for the insertion of the
same.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
14th March 1878.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN COMBINATION LOCKS." A com-
munication from abroad by Alfred Edward Peters, of Moncton, County of West-
moreland, Province of New Brunswick, and Dominion of Canada.
The object of this Invention is to furnish for doors, drawers, trunks, safes, post-
office boxes, and other purposes, an improved combination lock that may be set
with great facility without giving an opportunity to be picked, as the interior
parts cannot be reached by tools, and which is of greater simplicity of construction
than the combination locks at present in general use, so that by its cheaper manu-
facture it may be applied to a number of domestic purposes for which the former
locks are too expensive.
The Invention consists of a spring-acted roller or cylinder with interchangeable
pins that are acted upon by spring bars or fingers depressed by sliding set pins
entering through perforations of the face plate. The set pins are returned by
auxiliary springs and retained in position, so that only one set pin may be depressed
at a time by sectional guard plates that bind around the pins. The spring fingers are
engaged by a laterally sliding and toothed locking bar that releases the preceding
spring as soon as any one of the remaining springs is depressed, securing thereby
the return of the roller, except when the correct combination of set pins is depressed
in regular succession, which prevents the return of the roller, and allows finally,
by means of a cam at the end of the same, the throwing of a bolt.
In the accompanying Drawing,-
Figure 1 represents a front of the improved combination lock; Figure 2 a side
view.
Figure 3, a sectional elevation with actuating mechanism detached; and Figure 4,
a rear view of the same with rear face plate detached.
Figure 5 is a horizontal section of the lock on line x, x, Figures 4; Figures 6 and 7
are vertical transverse sections of the same on lines y, y, and z, z, Figure 4; and
Figure 8 is a detail view of the sliding guard plates that allow only one of the set
pins to enter the lock.
Similar letters of reference indicate corresponding parts in the several Figures.
A represents the casing of the improved combination lock for doors, trunks,
boxes, &c., which casing is preferably provided at the face part with a raised part
B having a series of perforations a that are numbered or lettered, and which serve
either to guide a corresponding number of projecting set pins C having enlarged
and conical inner heads with smaller end pins, or to admit the insertion of a key
pin of suitable thickness to set the combination thereby. Behind the holes a are
applied to the inner side of the face plate a series of spring bars or fingers D, which
correspond in number with the holes a, and are fastened at one end and free at the
other, so that by depressing a set pin, or inserting the key pin, the corresponding
spring finger is depressed. A number of sectional guard plates C¹ embrace the
conical ends of the set pins C, and slide in a guide recess of the raised part B at the
outer side of the casing, said guard plates serving for the purpose of allowing only
one of the set pins to be depressed at one time, as thereby the remaining guard
plates are forced sufficiently apart in opposite directions by the contact of the guard
plates, so that the set pin may enter and depress the spring finger. When more
than one of the set pins are pressed upon, the guard plates cannot give way, and
lock thereby the pins rigidly in position, barring their entrance into the lock. This
forms an essential feature in the successful working of the lock, as it compels the
depressing of the set pins and spring fingers successively one after the other.
A toothed and recessed bar E is placed below the entrance holes, and at right
angles and transversely to the spring fingers D, so that the latter may enter into

page_text: the corresponding teeth when depressed, and be retained by a recess at the base of
each tooth.
A second recess near the tapering head of the tooth forms a kind of safety recess
to produce a click by the spring, and mislead the ear when anyone is trying to
tamper with the lock by attempting to get a clue to the combination by the sense
of hearing.
The toothed locking bar E of the fingers slides in supports E', and is acted upon
by a spring b that carries the bar by the depression of a spring finger D sidewise
till the same has passed into the base recess of the tooth, where it is locked by the
bar, releasing at the same time any spring bar that has before been locked in the
same manner, so that only one spring at one and the same time may be retained
thereby. Between the spring bars D and casing A are interposed shorter auxiliary
springs d that return the set pins to the normal position in the raised part B as soon
as the spring bar D is locked by the bar E.
same,
At the end of the spring fingers D, and parallel to the locking bar E, is arranged
a roller or cylinder F that turns in the same supports as the locking bar, and is
acted upon axially by a spiral spring e. The roller F is provided with a number of
socket holes that are bored in the circumference in line with the centres of the
spring bars D. Into these holes may be, interchangeably screwed or otherwise,
applied short pins f, of which as many are used as there are set pins and spring bars.
These pins may be set into any desired combination that is possible between the
number of holes employed, a very large number of different combinations being thus
admissable. A fixed pin f¹ that is placed in line with one of the longitudinal row
of pin holes, but between two adjoining spring bars, so as not to be engaged by the
is thrown by the spiral spring e of the roller against a stop f' of the casing.
The combination by which the pins of the rollers are set has to proceed from the
line of holes in which the stop pin is arranged. When, for instance, the lock is
made with five set pins and a corresponding number of spring bars and locking
teeth, five longitudinal lines of pin holes have to be arranged on the roller. When
more set pins are used a larger number of lines of holes has to be arranged on the
roller, the pins being secured into the holes, according to the combination of figures
selected, and in consecutive order in the longitudinal rows of holes, starting from
that in line with the top pin, one pin only however being set into each row of holes.
The roller F has at its opposite end a cam F¹ that engages a spring acted plate F2 of
the bolt G whenever the roller is brought by the successive depressions of the
spring bars engaging the pins of the roller into the required position, the cam
then finally lifting the plate F2 and allowing it to slide over a stop plate G¹ of
the casing, or throwing the bolt back by a crank pin g with an outer button g'. It
is only by raising the spring plate of the bolt by the cam that the bolt can be
thrown back and the lock opened, this being prevented in any other position of
the roller. When therefore the set pins are depressed, or the key pin inserted in
regular succession, according to the combination that has been selected, the spring
bars are depressed, striking in this case one pin after the other on the roller, and
retaining the roller in position by the consecutive contact of the spring bars and
pins, until the same is fully turned, and admits, by the action of its cam end of the
bolt being thrown back. If however any other spring bar be depressed, or the
regular succession of set pins not kept up, the preceding spring bar is released, and
the roller instantly carried back to its original position against the stop; or the
roller is not affected at all, as no pin is in the way of the depressed spring bar.
Whatever spring may be depressed, the roller cannot be turned so as to open the
bolt without the use of the combination selected.
The lock may be set to a different combination by removing the back plate and
changing the pins in the rollers accordingly.
When it is desired to set the lock to a combination of less figures than there are
spring bars, the stop pin has to be set into a hole farther from the original row and
closer to the cam.
For closing the lock the bolt is thrown, and any one of the set pins depressed, so

page_text: that the last retaining spring bar is released and the roller carried back into its
original position for locking the bolt. This construction furnishes a combination
lock of small and neat shape that may be conveniently used for various applications,
as it offers the advantage of requiring no key, and also effectually prevents all
tampering with the lock, as there are no exterior openings for the insertion of any
tool with this object.
Having described the nature of the said Invention and the manner of performing
the same. I declare that what I claim as the Invention to be protected by the herein-
before in part recited Letters Patent is,-
1st. A combination lock composed of a series of spring bars or fingers capable of
being depressed at the free ends of a transversely sliding and toothed locking bar,
and of an axially turning spring roller or cylinder with interchangeable pins, sub-
stantially in the manner described and for the purpose specified.
2nd. The combination of the spring bars or fingers capable of depression by set
pins or key pin inserted through holes of the face plate, with a transversely sliding
and spring-acted locking bar, having teeth and recesses corresponding to the number
of spring bars, so as to lock each spring when depressed, and release the same by the
locking of the next spring, substantially as specified.
3rd. The combination of a series of sliding and spring-acted set pins guided in
holes of the face plate, of a number of spring bars capable of being depressed at
the free ends, of a transversely sliding and toothed locking bar, of an axially
turning spring roller having interchangeable pins and cam end, and of the spring
plate of the locking bolt, substantially as specified.
4th. The combination of the sliding and spring-acted set pins guided in holes of
the face plate, with a number of sliding sectional guard plates fitted around the said
pins so as to admit the depression of one set pin only at the time, substantially
as described.
5th. The combination of the spring bars capable of being depressed at the free
ends of the transversely sliding and toothed locking bar, and of the axially turning
spring roller having longitudinal rows of holes, interchangeable pins, and an inter-
mediate stop pin, in connection with a fixed stop of the casing, to return the roller to
its orignal position in case the set pins are not depressed in proper succession,
substantially in the manner described, and for the purpose specified.
6th. The transversely sliding locking bar E having teeth that are recessed near
the base and head to retain the spring bars and produce clicks, substantially as
described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Fourteenth day of March, in the year of our Lord
One thousand eight hundred and seventy-eight.