Year: 1898

page_text: Date of Application (in United Kingdom),-26th Oct., 1898
Complete Specification Left, 20th Dec., 1893—Accepted, 8th Apr., 1899
I, ERNST MICHAELSEN, of 26, St. Anneplaks, Farimagsgade, Copenhagen, Den-
mark, Wholesale Dealer, do hereby declare the nature of this invention to be as
follows:-
The object of this invention is a device in connection with spring-locks of the
Yale system, whereby it is made possible, after the door has been shut, to secure
the bolt in its forward position in such a manner that it will be quite impossible
by any undue influence to push it backward from the outside and thereby open the
door.
In the present spring-locks of the Yale system it is quite possible for example
by inserting a flat tool between the door and the door-frame or by introducing
through a hole in the door a suitable instrument that may catch hold of the knob,
to open the door, a drawback, which is entirely obviated by the present invention.
In order that. the invention may be clearly understood there will be first
described the mechanism of an ordinary spring-lock of the Yale system.
In the lock-casing is a sliding-bolt actuated by a spiral spring one end of which
prosses against a shoulder on the bolt and the other end against a cross-bar in
the casing. The rear of the bolt is formed as a forked link; the ends of the
branches being bent inward so as to form hooks. In the bottom part of the casing
is arranged a spindle carrying at its outer end a knob by means of which the
sindle can be turned round from the inside of the door. The other end of the
spindle is provided with a plate shaped so as to present two projections just in
front of the above mentioned hooks. Another plate of the same shape is fixed on
to the lower extremity of a plate or bar the upper end of which is connected in
a suitable manner with the locking-cylinder. The arrangement is such that the
two plates may be turned quite independently of one another and it is obvious
that the bolt may be pulled in or withdrawn either by turning the.knob and the
first mentioned plate connected therewith or by turning the plate or bar connected
with the second mentioned plate and the locking-cylinder.
In the former case the lock is opened from the inside and in the latter case from
the outside.
In the ordinary Yale system locks the two plates, are normally, kept in the same

page_text: position in front of the hooks at the rear of the bolt and it is evident that there
is nothing to prevent the bolt from being pushed backward if in some way or
other the bolt-head projecting beyond the casing is acted upon, for example by
means of a flat tool inserted between the door and the door-frame.
Now the object of this invention is to avoid such facilities for opening and
consists in arranging a suitable stopping device behind one of the aforesaid hooks.
For this purpose according to one arrangement the spindle besides being ar-
ranged to rotate is also made movable longitudinally so that it may be pulled
out a certain distance in the direction of its axis. The spindle instead of being
provided with a plate shaped to present two projections in front of the hooks
on the bolt, is provided with an arm of suitable shape and between this arm and
the bottom of the lock-casing is arranged a spiral spring that is compressed when
the knob is pulled out. In the lower part of the right-hand hook is cut an
angular notch which will allow the arm to pass when the spindle is pulled out and
turned. The left-hand hook is at its upper part provided by an angular notch
forming a passage for the arm, when the latter is in its raised position.
The distance through which the spindle may move in the direction of its axis
is limited in any suitable manner as for example by the complete compression of
the spiral spring. The plate on the extremity of the plate or bar is dispensed with
according to this invention and the free end of the plate or bar projects into a
slot made in the upper end of the spindle. This slot is at the centre of the same
width as the plate or bar and is from there to the periphery enlarged so as to
form angular spaces on the lower right and upper left sides of the space occupied
by the plate or bar when in its central position. This shape of the slot will allow
the spindle together with the arm to be turned round a certain distance before
the movement is impeded by the plate or bar which is kept in position by the
locking-cylinder, the distance being such as to enable the arm on the spindle to be
moved from the position in front of the aforesaid right hand hook to the position
behind it whilst the sides of the slot are moving through the angular space.
The operation of the mechanism is as follows:-
If the lock has to be shut from the outside, after the door has been closed,
a complete turn is given to the key towards the left. Together with the key the
locking-cylinder and the plate or bar are turned and, as soon as the plate or
bar has been turned through the angular space of the slot in the spindle it will meet
the sloping surface of the slot and then carry with it the spindle. When the key has
made one complete turn and is removed from the lock the tumbler can again fall into
the locking cylinder and the lock will be shut. The arm is now in the position behind
the hook and cannot be turned backward as the plate or bar which is kept in position
by the locking-cylinder, will prevent the turning of the spindle. When in this
position the arm will prevent the bolt from being pushed backward by any outside
influence. The opening of the lock is offected from the outside by giving the
key a complete turn to the right. The same operation may be effected from
the inside by first pulling the spindle forward or outward by means
of the knob, until the arm is opposite the notch in the right hand
hook. The spindle is then turned round to the left the arm passing
through the said notch. On account of the above described shape of
the slot in the spindle the turning of the latter for the required distance
may be effected without influencing the plate or bar. Actuated by the spring
the spindle will assume its normal position and thus bring the arm in front
of the right hand hook, two other surfaces of the incision being now, brought
adjacent to the plate or bar.
The spindle, without being prevented from doing so by the plate or bar, may
now be turned to the right whereby the arm pulls the bolt backward and the
door is unlocked. If it is desired to shut the lock from the inside the arm is
first brought into the position behind the right hand hook by pulling the knob
until the arm is opposite the notch in the said hook and then the spindle is turned
to the right until it assumes the said position. By now letting the spindle be

page_text: moved back to its normal position through the action of the spring the arm
will be placed directly behind the hook, a further movement of the spindle to
the right being prevented by the aforesaid plate or bar.
The bolt will therefore in this case also be secured against being pushed
backward by foul means. The notches in the hooks are so arranged that the
bolt-mechanism may be reversed so that the lock will be either right or left-hand.
For the purpose of bringing the arm from the position in front of the right hand
hook to the position behind it and vice versa, the spindle may be arranged so as to
be pushed in against the lock-casing instead of being pulled out away from
the same, the notches in the hooks being arranged accordingly.
Dated this 26th day of October 1898.
I, ERNST MICHAELSEN, of 26, St. Annæplads, Copenhagen, Denmark, Wholesale
Dealer, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement:-
This invention relates to a device in connexion with a spring-lock of the Yale
type, whereby it is rendered possible after the door has been shut, to secure the
bolt in its forward or shot position in such a manner that it will be quite
impossible by any undue influence to push it in from the outside and thereby to
open the door.
In Yale spring-locks as at present constructed, it is quite possible-for example,
by inserting a flat tool between the door and the door-frame-to open the door,
a drawback which is entirely obviated by the present invention.
In order that the invention may be clearly understood there will be first described
the mechanism of an ordinary Yale spring lock, of which Fig. 1 of the accom-
panying drawings is a plan of the locking-mechanism and Fig. 2 is a section
according to line 1-1 of Fig. 1.
In the lock-casing a is a sliding-bolt 6 actuated by a spiral spring e, one end of
which presses against a shoulder on the bolt and the other end against a cross-
bar d of the casing. The rear of the bolt is formed as a forked link e, the ends
of its branches being bent inward so as to form hooks f, f. In the bottom part
of the casing is arranged a spindle h carrying at its outer end a knob i by means
of which the spindle can be turned round from the inside of the door. The other
end of the spindle is provided with a plate o shaped so as to present two projections
just in front of the hocks f, f¹. Another plate p. of the same shape as the
plate o, is fixed to the lower extremity of a bar k, the uprer end of which
is connected in a suitable manner with the locking cylinder, which is not
shown in the drawings. The arrangement is such that the two plates and p
may be turned quite independently of each other, and it will be obvious from the
drawings that the bolt may be pulled in or withdrawn either by turning the knob i
and the plate o connected therewith, or by turning the bark connected with
the plate and the locking-cylinder.
In the former case the lock is opened from the inside and in the latter case
from the outside.
n
In the ordinary Yale locks the two plates and p are always in front of the
hooks f and fl as shown in Fig. 1, and it is evident that there is nothing to prevent

page_text: the bolt from being pushed inward if in some way or other the bolt-head pro-
jecting beyond the casing is acted upon-for example, by means of a flat tool
inserted between the door and the door-frame.
Now the object of this invention, which is illustrated by Figs. 3 and 4 (of
which Fig. 3 is a view corresponding to Fig. 1 and Fig. 4 is a section corresponding
to the line 2/2 of Fig. 3), is to prevent a door from being opened in this manner,
and according thereto a suitable stopping device is provided that can be placed
behind one of the aforesaid hooks.
For this purpose, the spindle h, besides being arranged to rotate, is also made
movable longitudinally, so that it may be pulled out a certain distance in the
direction indicated by the arrow in Fig. 4. The spindle h, instead of being pro-
vided with a plate such as o, is provided with an army of the shape shown in
Fig. 3, and between this arm and the bottom of the lock-casing is arranged a
helical spring m that is compressed when the knob i is pulled outward. In the
lower part of the right-hand hook f is cut an angular notch n, which will allow
the arm to pass through the hook f when the spindle h is pulled out and
turned. The left-hand hook f is, at its upper part, also provided with an angular
notch n forming a passage for the arm.g when the latter is in the position shown
in Fig. 4.
The distance through which the spindle h may move longitudinally is limited
in a suitable manner as, for example, by the complete compression of the
spring m. The plate on the extremity of the bar is dispensed with according
to this invention, and the free or lower end of the bar projects into a slot 7
made in the upper end of the spindle h. This slot is at the centre of the same
width as the bar k and is from there to the periphery enlarged so as to form upper
and lower angular spaces, each of the angle v, on the right and left sides respec-
tively of the space occupied by the bar when in its central position, in which it
is shown in Fig. 3. This shape of the slot will allow the spindle h; together with
the arm g, to be turned through a certain angle e, before the movement is impeded.
by the bark, which is kept in position by the locking-cylinder; the angle v.
is such as to enable the army on the spindle to be moved from the position
shown in full lines in Fig. 3 to the position indicated in dotted lines therein,
whilst the sides of the slot are moving through the angle v.
The operation of the mechanism is as follows:
If the lock has to be shut (i.c., fastened) from the outside, after the door has
hern closed, a complete turn is given to the key in the direction indicated by
the arrow in Fig. 3. Together with the key, the locking-cylinder and the bar k
are turned. and, as soon as the bar has been turned through the angle , it
will meet the sloping surface of the slot and then carry with it the spindle,h.
When the key has made one complete turn and is removed from the lock, the
pins can again fall into the locking-cylinder and the lock will be shut. The
arm g is now in the position g (behind the hook) indicated in dotted lines, and
cannot be turned backward as the bar k, which is kept in position by the locking-
cylinder, will revent the turning of the spindle h. When in this position,
the arm g will prevent the bolt from being pushed inward by any outside influence.
The opening (i.e., unfastening) of the lock, when the arm g is in the position g',
is effected from the outside by giving the key a complete turn in the direction
opposite to that indicated by the arrow in Fig. 3; but in order to open the door
the key must be turned slightly further in the same direction. The opening of
the door (when the arm is in the position g¹) may be effected from the inside
by first pulling the spindle h outward by means of the knob (in the direction)
indicated by the arrow in Fig. 4), until the arm is opposite to the notch n
in the hook f. The spindle h is then turned round in the direction indicated by
the arrow in Fig. 3, the arm 9 passing through the notch n. On account of
the above described shape of the slot 7 in the spindle h, the turning of the latter
for the required distance may be effected without influencing the bar k. Actuated
by the spring m, the spindle will assume its: normal position and thus bring the

page_text: arm g in front of the hook f, as shown in Fig. 3, the two other surfaces of the
slot being no.y adjacent to the bar k.
The spindle h, without being prevented from doing so by the bar k, may now
be turned in the direction opposite to that indicated by the arrow in Fig. 3, so
that the army will pull the bolt inward and thereby allow the door to be opened
If it is desired to shut (i.c., fasten) the lock from the inside the arm g is first
brought into the position g¹ behind the right-hand hook f by pulling out the knob i
until the arm g is opposite to the notch in the hook f and then turning the
spindle in the direction opposite to that indicated by the arrow in Fig. 3, until
it assumes the position g¹. By now letting the spindle h be moved back to its
normal position through the action of the spring m, the arm g will be placed
directly behind the hook f, a further movement of the spindle h in the direction
opposite to that indicated by the arrow in Fig. 3 being prevented by the bar k.
The bolt will therefore in this case also be secured against being improperly
moved inward.
The notches n and n¹ in the hooks'f and f¹ are so arranged that the bolt-mechan-
ism may be reversed, so that the lock may be either right or left handed.
It is obvious that it might be arranged that the arm g would be brought from
the position in front of the right-hand hook f into the position g¹ behind it and
vice versa, by pushing the knob i in against the lock-casing instead of pulling it
away from the same, the notches n and n¹ in the hooks being arranged accordingly.
Having ow particularly described and ascertained the nature of the said in-
vention and in what manner the same is to be performed, I declare that what I
claim is:
1. A spring-lock of the Yale type, in which, for actuating the bolt b, there is
provided only one arm that, by means of the knob or the key, can be brought
into such a position (the locking position) as to prevent the bolt from being pushed
inward by an undue pressure on the bolt-head.
2. A spring-lock of the kind indicated in the preceding claim, in which the
knob-spindle is made movable longitudinally and is kept in its normal position
by a spring, so that, owing to a slot in one end of the said spindle, the spring-
Fock may be used in the ordinary way, whilst, after having been moved longitu-
dinally the knob-spindle may be turned so as to carry the arm g through a notch n
in the rear portion of the bolt, the said arm being brought into the locking-position
when the spindle h, under the influence of the said spring, assumes its normal
position.
3. A spring-lock of the kind indicated in Claim 1, in which the rear portion of
the bolt is provided with a notch n so that, by means of the key, a turn may
be given to the army in the direction opposite to that for opening the lock,
and the arm may thereby be brought into the locking-position.
4. The improved locking-mechanism constructed, arranged, and operating as
hereinbefore described with reference to and shown in Figs. 3 and 4 of the accom-
panying drawings.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.