Improvements in Locks.
Year: 1892

page_text: Date of Application, 12th May, 1892-Accepted, 6th Aug., 1892
Improvements in Locks.
1, EUGENE CHARLES SMITH, of 33 West Washington Square in the City of
New York, State of New York, United States of America, Mechanical Engineer,
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 :-
My invention relates to improvements in locks, especially the kind known as
cylinder locks, and the purpose of the invention is to adapt the lock cylinder to be
used with means for automatically projecting the bolt by the closing of the door,
drawer, etc. to which the lock is applied. I effect this adaptation by combining a
lever, which I term an "idler" with the lock cylinder in such manner that said
idler is on the one hand capable of motion independently of the lock cylinder, and
on the other hand is adapted to be engaged by said cylinder for the purpose of
moving the bolt through the agency of the cylinder. The said idler is connected
with the bolt and also with the strike lever by which the bolt is projected when the
door is closed, and the motions of the bolt are effected through the idler. The
combination has the great advantage that it allows of the use of a cylinder type of
locks with automatically closing mechanism, and square ended bolts which cannot
be pressed back by inserting thin metal plates in the socket in the door jamb so as
to surreptitiously open the door. Since my idler is adapted to be used with any
kind of lock cylinder, I hereinafter first show it applied to a cylinder lock having
tumblers and a locking bar similar to those shown and described in my Patent of
Great Britain, No. 17,630, and bearing date November 5th, 1889, and secondly to
the common pin-cylinder lock.
My invention also relates to improvements in the form of the tumblers, whereby
a surreptitious opening of the lock by blank keys or picks is rendered more
difficult.
Referring now to the drawings which accompany the Specification.
Fig. 1 is a plan view of the idler, strike-lever, bolt and their connections, when
the bolt is drawn back and the door opened.
Fig. 2 is a view of the same as seen from below.
Fig. 3 is a view of the same parts as in Fig. 1, but the bolt is shown projected,
and the strike lever pushed back.
Fig. 4 is a view of the same as seen from below.
Fig. 4 is an enlarged view of a key of my locking-bar cylinder-lock.
Fig. 5 is a perspective view of the interior of a lock showing the idler applied to
my locking-bar cylinder.
Fig. 6 is a perspective view of the same, but with the idler separated from the
cylinder, and broken away to show its sectional form.
Fig. 6A is a perspective of the key barrel or cylinder.
Fig. 7 is a longitudinal section of the lock, but the key cylinder and locking-bar
are shown in elevation.
Figs. 8, 9, and 10 are plan views of the idler and tumblers, looking toward the
right end of Fig. 7, and showing first, the bolt drawn back but tumblers locked ;
second, bolt shot forward and tumblers locked; third, bolt drawn back and
tumblers unlocked.
These views show the idler as seen when one looks into the lock and toward the
right end of Fig. 7.
Figs. 11, 11 and 12 are views of the tumblers enlarged and as seen by one
ooking into the lock toward the left end of Fig. 7. Fig. 11 shows the tumblers
locked, Fig. 114 the tumblers unlocked, but the cylinder not yet rotated; and

page_text: 14 the tumblers unlocked and the cylinder rotated.
Figs. 8 and 9, and Fig. 12 to Fig. 10.
Fig. 11 corresponds to
Figs. 13, 14, 15, are plan views of the idler, with the locking-bar and cam, aud
show the idler, first when the bolt is shot forward; second when the bolt is drawn
back, and the lock cylinder is toward the right; third, when the bolt is drawn
back and the lock cylinder is. toward the left.
Figs. 16, 17 and 18, are sections on the line a.
respectively.
2, of Figs. 13, 14, 15,
Figs. 19 and 20. are perspective. views of the back and front respectively of the
locking-bar and cam, much enlarged, and Fig. 21 is a longitudinal section of
the same.
Fig. 22 is a plan and section of the front cap of the cylinder; looking toward its
under side, and showing the device for changing the combinations.
Fig. 23 is the plan view of a washer.
Figs. 24, 25 and 26 show the idler applied to a pin-cylinder lock. The figures
show, first a longitudinal section, second a plan (from the left) of the end of the
cylinder and the cam: third, a plan view of the idler looking from the right. The
idler is enlarged.
Figs. 27 and 28 (Sheet 2) are enlarged details of a tumbler and locking bar;
and showing the said tumbler first in the neutral position, the locking bar being in
the locked position, second, as moved forward in an attempt to surreptitiously open
the lock, the locking bar being slightly moved.
Describing first the idler and its connections with the lock and strike-lever, and
which are applied to any cylinder locks;
A is the lock, on the door B. C is the bolt, guided by the pin 2, in the slot 1,
of the bolt tail. c. D is the "idler," which is in effect a lever, pivoted on a pin 5,
so as to oscillate freely and having a knob 6 which engages a socket 3 in the bolt
tail, C, and also an arm 7 opposite to said knob, 6, in which, with easy working fit
is set the pin 8, projecting at right angles from the idler and having a flat head 9,
with a hole 10, through which passes with easy fit one end of a connecting rod 11,
which is pivoted at its other end in the face, e, of the strike lever E. A spring 12
is coiled around the connecting rod 11, between the head 9 of pin 8, and the
shoulder 12 of said connecting rod. Said strike lever E, is pivoted to the case
at 13, and has a cam face e¹, which normally projects through a slot in the front of
the lock case and so as to be engaged by the strike plate, f, of the door jamb F,
when the door B is closing. The other face e, of said strike lever E is struck as
an arc of a circle, from the pivot 13. as a centre. Now, the strike lever E
projecting, the bolt, C, drawn back, and the idler D inclining to the right as in
Fig. suppose the door B is closing; then the strike plate, /, will push back the
strike lever E to the position of Fig. 4, thereby compressing the spring 12, and
tending to incline the idler D to the left and project the bolt, C. But the bolt
cannot project until it comes exactly in line with the socket 14 in the door jamb F.
When so opposite, the bolt C, immediately shoots into said socket 14, the idler
takes the position of Fig. 3, and the door is locked. To open the door, assume
that, the idler D is turned to the right by the lock mechanism acted on by the
proper key, in the manner hereinafter explained. Thereby the idler will again
come to the position of 'Fig. 1, and the bolt C will be drawn back by said idler.
At the same time the spring 12 will be compressed and will tend to project the
strike lever E,. to the position of 'Fig. 2. But the strike lever E, cannot so project
until the door B; is sufficiently opened to bring the strike lever E clear up the
strike plate, f. When the door is so opened the strike lever E immediately fliès
out to the position of Fig. 2, and the door is. ready to be again closed.
To energize the motion of the idler D, a coiled spring, 17; (see. Figs. 13, 14, 15
Sheet 4) is employed having its one end freely set on a pin 18 that is fixed in the
back of the idler D, and its other end set on a pin 19 that is fixed in the lock case,
in line with the midway position of the idler D. Thus, as the idler D approaches
the middle position it compresses the spring 17, and as the idler moves to either

page_text: the right hand or the left hand of the middle position the spring 17 impels it to
the full limit of its throw.
Figs. 5 to 23 inclusive are views of a lock wherein my said idler is applied to
my locking-bar cylinder lock. Describing the same, the bolt, C, strike lever E,
and their connections with the idler D are as hereinbefore explained, and the
idler D is preferably of cylindrical shape, with a deep circumferential rim 4,
(Fig. 6) in which is a socket 65 for the locking-bar cam O, as will be hereinafter
described. The idler D is pivoted freely, on the pivot 5 which is fixed in the back
lock plate A¹, passes up through the hole 5* in the idler D and serves also as the
pivot of the cap G₁ of the lock cylinder. On said pivot 5 is the washer 5° to
separate the idler D from the plate A'. In said idler D is a through and through
slot 52, which is struck on the arc of a circle from the pivot 5 as a centre, and
coincides when the idler is inclined to the right, (Figs. 14, 15) with a similar
slot 55 in the plate A', (Figs. 16, 17, 18). The length of said slots 52 and 55 is
equal to the throw of the idler D between its extreme positions. The lock
cylinder consists of the cylindrical caps G and G₁ which are rigidly connected
together by the screw 16, indicated by heavy dotted lines in Fig. 7 and placed to
one side out of the way of the tumblers, K. Said caps G, G', are held a proper
distance apart by the longitudinal pins 14, 15, 16, 16, 17, which have their one
end threaded into the cap G and their other end entering a proper distance into
corresponding sockets in cap G¹. The pins 14, 15, and the screw 16 serve as
supports for the tumbler springs 30, and the pins 16 and 17 as stops to limit the
motion of the tumblers, K. In the cap G is a key slot, 62, (see Fig. 5) by which
the key is to be inserted to unlock the lock, and also another slot 63, through
which the key is to be withdrawn, and a new key to be inserted when the
combination is to be changed as will be hereinafter described. The slot 63 is
normally covered by a plate R, in a socket 75 in the under side of the cap G. A
key cylinder H (Fig. 6) slotted at 22, in the ordinary manner, traverses the
space between the caps G, G', and turns freely by reason of its neck h, fitting
loosely in the hole as in cap G, and its rear end fitting loosely the hole g* in cap G¹,
and said key cylinder H has a shoulder which prevents its displacement. Said
key-cylinder H, is also. the axis of the tumblers K, (see Figs. 11 11 & 12)
whereof there are usually twelve in each lock, and each of said tumblers is made of
sheet metal, preferably of circular shape, and perforated with the central round.
hole, K, which fits easily over the key cylinder H. The arc of oscillation of said
tumblers K is made an aliquot part of a circumference, as 40° or the ninth part
of a circumference, and around said. central hole k, are nine slots, 37, 38, 39, 40,
41, 42, 43, 44, 45, spaced at an angular distance apart equal to the arc of
oscillation of the tumblers. If the arc of oscillation of the tumblers was say a
tenth or twelfth part of a circumference, there would be ten or twelve slots
around the central hole k, and so on according to the oscillation of the tumblers.
The angular distance between the slots is always equal to the arc of oscillation of
the tumblers. Now the tumblers having been originally placed with all the
slots 37 coinciding it is evident that if any tumbler be moved through 40° its slots
will still exactly register with the slots of the other tumblers, and consequently
when some of the tumblers are locked and some unlocked, the slots will give no
indication of which tumblers are in the one or the other position. Each of said
tumblers K, has a projection 29, (represented in the locked tumblers by 29ª,
Figs. 11 & 12) to actuate the locking-bar M, and also a projection 28
(represented by 28" in the locked tumblers) to prevent surreptitiously moving the
locking-bar, as will be hereinafter explained, and each tumbler also has
projections', on the one or the other of which press the ends of said
springs, 30, according to the position of the tumblers. There is one of said
springs 30 for each tumbler, and the end 30° of the innermost spring, or that to
the right in Figs. 5 & 6 is extended and serves also as a spring for the locking-
bar M. Said tumblers K. are placed on the key cylinder H, as said, and with a
washer L between each pair of tumblers, K, and the washers L, are of thin brass.

page_text: of circular shape, and of larger diameter than the tumblers K, so as to form
Each
spaces between each pair of washers, in which are guided the springs 30.
washer L (see Fig. 23) has a central hole, which slips over the key cylinder and is
of greater diameter than the sweep of the bits of the key, and also has the
segmental hole 24 through which passes the locking-bar M, also the hole 25 for
the screw 16, and the holes 26, 27, 27ª, 27b for the said pins 15, 14, 17, 16*
respectively. Said locking-bar M is pivoted adjacent to and so as to be engaged
by the tumblers K on the pin 35, which passes through the lengthwise hole 51 in
said locking-bar M, and projects beyond the cap G', and so as to pass through the
slot 52 in the idler D and enter the slot 55 in the plate, A'. Said locking-bar M
(see Figs. 19, 20 & 21) traverses the space between the caps G, G¹, is straight
longitudinally, and in cross section is a bent lever, having arms 33, 34, and the
space 33ª between the arms. The front end of said locking-bar, or that to the left,
is formed with a round side 31 which is adapted to enter a socket 36, in the
cylindrical sleeve a² of the front plate A, and with a flat side 32 which will not
enter said socket 36; and the rear or right end of the locking-bar M is fashioned
with the angular surfaces 44, 46, (Fig. 19) on one or the other of which surfaces
the spring 30 presses according to the positions of the locking-bar. The purpose
of said spring 30 is to energize the movement of the locking-bar M and ensure
that said locking-bar M shall rotate to the full limit of its throw in either
direction. In the right end of the said locking-bar M the hole 51 is enlarged
into a cylindrical cavity 49, (Fig. 21) to receive a coiled spring N, and also the
sleeve o of the cam O, and the right end of said locking-bar M is also cut away on
one side to form the depressed plane surface, m, and the shoulder m'. But in
place of the shoulder m', the end of the locking-bar M may be a plane surface
with a pin as a substitute for the said shoulder. One end of said spring N is
fixed in the locking-bar M, and the other end is fixed in the sleeve of said
cam O, and the spring N is so coiled that its tension tends to turn the cam O
against the shoulder so that the cam O projects beyond the locking-bar M, as
seen in Figs. 13 and 19, also in Fig. 9. Said cam O is formed as a flat segment of
a circle, and has as said, the pivotal sleeve, o, which fits easily into the hole 49 of
the locking-bar M, and said sleeve O has a hole through which the axial locking-
bar pin 35 passes, as seen in Fig. 21.
It will be understood that when the lock is assembled the end of the locking-
bar M and the cam O, will enter freely within a socket 9' in the cap G', (Fig. 6),
and that the cap G, will fit within the rim 4 of the idler D so that the cam O is
also within said rim, (Figs. 5 & 7); the pin 35 will pass through the slot 52 in
the idler D and into the slot 55 in the plate A', and that the cylindrical sleeve a²
of the plate A will pass easily over the cap G, and also over the left end of the
locking-bar, M, said locking-bar and tumblers being first in the unlocked position
of Figs. 9 and 11ª. Before the lock is used, and usually before it leaves the
factory, it is set on some one combination by locking it with a proper key, which
key is inserted through the key slot 63 and turned back to the slot 62 as will be
hereinafter explained. Thus the certain combination of tumblers and the locking
bar M are turned to the locked position of Fig. 11, (corresponding to Fig. 8)
wherein the round side 31 of the locking-bar M enters the socket 36 in the
sleeve a², and thereby prevents turning the cylinder until the lock is opened by the
same key as set the combination.
The operation is as follows: Suppose the lock to be on a door, drawer, etc., and
that the bolt is drawn back, and the strike lever projected as in Fig. 2, the certain
combination of tumblers and locking-bar being locked as in Fig. 11, or 8, and the
idler D inclined to the right so that the socket 65 is not in line with the cam O,
consequently the rim 4 of the idler D holds in cam O so that the spring N cannot
project said cam beyond the locking-bar. Now the door etc. is closed, thereby
forcing back the strike lever E, and projecting the belt, C, as herein before
described, and at the same time turning the idler D to the left as in Figs. 9, and 13,
so that the socket 65 is in line with the cam O. Immediately the spring N turns the

page_text: said cam into the socket 65 and thus locks the idler D and prevents the forcing
back of the bolt until the cam O is drawn down out of the socket 65 by the proper
key, as will be hereinafter described.
The door is now locked. To unlock it, the key that was used to set the com-
bination of tumblers, or its exact duplicate, is inserted in the key cylinder H by
the slot 62 in the cap G, and turned in the direction of the arrow in Fig. 11. Its
bits as 1, 2, 3 Fig. 4 will engage the slots 37 of the locked tumblers, and will
turn the said tumblers in the direction of the arrow, and at the same time the
projections 29 of said locked tumblers will turn the locking-bar M to the position
of Fig. 11 so that round side 31 passes down out of the socket 36, and the
cylinder will be free to turn. At the same time the shoulder m¹ of the locking-
bar M has turned the cam O down out of the socket 65. Now continuing to turn
the key in the same direction the said tumblers cannot turn further because their
said projections bear against the pin 16". Consequently the cylinder turns as a
whole, and the pin 35 being at the right end of the slot 52, but at the left end of
the slot 55 (see Figs. 13 & 16), it rotates the idler D in the same direction until
the motion of the cylinder is stopped by the pin 35 coming against the right end
of the slot 55 in the plate A¹. The idler D while so turning has drawn back the
bolt C, so that the door B can be opened, and has compressed the spring 12 which
again projects the strike lever E, as soon as the door B is sufficiently opened, as
hereinbefore described. The tumblers and locking-bar are now in the position
The lock is now
of Fig. 12 or Fig. 10, the cam O being as shown in Fig. 14.
opened, and the key is in line with the slot 63 in cap G, but the key cannot be
withdrawn because the slot 63 is covered by the plate R, (Fig. 22). Consequently
the key is turned backward, tending to turn the certain combination of tumblers
backward. But the tumblers cannot turn because the flat side 32 of the locking-
bar M immediately comes against the sleeve a². Therefore the cylinder turns backward
as a whole until further motion is prevented by the pin 35 coming against the left
end of the slot 55. While so turning the pin 35 has moved freely through the
slot 52 in the idler D without moving the idler. The cylinder is now in the position
of Fig. 11, wherein the locking-bar is directly in line with the socket 36 in the
sleeve a. Therefore by still turning the key in the same direction the certain com-
bination of tumblers corresponding to the bits of the key will be moved and their
projections 29, (29) will turn the locking-bar to the position of Fig. 1, so that its.
round side 31 enters the socket 36 in the sleeve a³, and locks the cylinder. At the
same time the turning of the locking-bar winds up the spring N, the cam O not
being able to turn because it is held in by the rim 4 of the idler D. The
mechanism is again in the position of Figs. 8 and 11, the key is in line with the
slot 62 in the cap G, and is taken out of the lock, which is now ready for another
closing of the door.
It is evident that there may be as many combinations of tumblers as there are
combinations of things mathematically possible from a number of things equal to
the number of tumblers; that for each combination there will be a separate key,
and that only that key will open the lock, which originally locked the combination
Besides
of tumblers. The combination can be changed in the following manner.
the slot 62 through the cap G¹, there is a second slot, 63, placed as stated in line
with the slot, 37, when the tumblers are unlocked and in the position of Fig. 11ª.
This slot 63 is covered by the plate, R, which is inserted loosely in the socket, 75,
in the under side of the cap, G, and is fixed on the pivot, r, which passes through
a hole in the cap G and has a slot in its head, for a screw driver. The plate R, is
of such size, and cam shaped, that it can cover the slot 63, but not the slot 62, and
there is a spring 60, which normally presses the plate R across the slot 63.
Now to change the combination some combination of tumblers and the locking-
bar M being in the locked position of Fig. H, the proper key is inserted and turned
in the direction of the arrow, until the tumblers and locking-bar are in the unlocked
position of Fig. 11ª. The arrival of the tumblers at this position is perceptible
to one turning the key, so that, the key being now in line with slot 63, he stops

page_text: turning and by a screw driver inserted in the pivot, r, turns the plate R so as to
uncover thesslot:63. The key is unowi taken out, and a new key with a different
combination of bits as indicated by the dotted lines Fig. 44 is inserted through the
slot, 63; and turned back, thereby setting new. combination of tumblers in the locked
position of Fig. 11, the side 31 of the locking-bar M at the same time again turning
up. into the socket 36. The new key is now taken out, leaving, the lock set on a
new combination.
The said projections:28 on the tumblers K prevent the surreptitious opening of the
lock by flexible blank keys or by picks in the following manner. Suppose some
certain tumblers K, to be locked as indicated by 29 in Figure 27, and other
tumblers to be unlocked as indicated by 28 in the same figure. Then will the top
of said projection 28 of each of the unlocked tumblers be just clear of the arm, 33 of
the locking-bar M (Figure 27). Now there is a little play between the projection 29
of said unlocked tumbler and the stop pin 16, so that if a flexible blank key is
introduced into the lock and turned in the direction of unlocking, some bits of said
blank will engage a recess in some of the unlocked tumblers and will begin to turn
such unlocked tumblers toward the left of the drawing whereby the projection 28
will be carried under the said arm 33 of the locking-bar M, until the projection 29
is arrested by the said pin, 16". Simultaneously other bits of said blank will have
turned some of the locked tumblers in the same direction, and their projections 29ª
will begin to turn the locking-bar M, as is fully explained, in my said Patent
No. 17,630 of 1889. But soon the arm 33 of the locking-bar M, comes hard down
on the said projections 28 of the unlocked tumblers, and the locking-bar M,
cannot complete its movement so as to free the locked tumblers, but will be held
fast so that the lock cannot be opened. Similarly, if a pick inserted in the lock
move any one of the unlocked tumblers to the left the lock cannot be opened.
As my idler is applicable to other cylinder locks, I show it in Figs. 24, 25
and 26 applied to Yale pin-cylinder locks. It will be understood that the bolt C,
and strike lever E, not shewn in said figures, and their connections with the idler,
are as herein before described, and that the idler D', oscillates on the axial pin 36,
which is set in the rear lock plate A and passes up through a central hole in the
idler D and enters a central hole in the end of the cylinder A. The idler D¹
oscillates and assumes positions corresponding to those shown in Figs. 13, 14 and
15, but since the motion of the idler has been hereinbefore fully described, I now
show only the position of Fig. 26, corresponding to the position of Fig. 13, wherein
the bolt is understood to be shot forward and the door locked, and the strike lever
pushed back. The said pin cylinder lock consists, as is well understood of the
fixed external case A¹, in which revolves the cylinder, A³. B', is the key barrel,
and 9, r, are the well known pins pressed down by the springs V, V, so as to hold
the cylinder A, from turning to draw back the bolt, until the proper key has raised
the pins. Now, I apply my idler to this pin cylinder lock in the following
manner; The idler D is as before preferably of circular shape, with the
knobs d', d, for connection with bolt and strike lever respectively, is pivoted as
said on the pin 36, and is formed with a circumferential rim 4 and depressed
surface 4*. In the rim 4 is a socket, 65, for engagement with the cam K¹. Said
cam K is pivoted on the pin 35 which is set in the end of the lock cylinder A',
and passes through the slot 52 in the idler D', and enters the slot 55, in the plate A³.
Said slots are struck on arcs of circles from the pivot 36 as a centre; are in length
equal to the throw of the idler and are in all respects similar to the corresponding
slots 52 & 55, in my locking-bar lock hereinbefore described. Said cam K', sets
within the rim 4, of the idler D' and also within a circular depression, a', in fixed
case A¹
In the wall of said depression a', is a socket a², into which the cam K¹
turns in certain positions of the cylinder A.. Said cam K' is shaped on one
side k as an arc of a circle struck from the pin 35 as a centre and the other side
may be straight as at k¹. In the case A' and within the limits of the socket, a', is
a pin a³ for engagement with the straight side, k, of the cam K. The aforesaid
sockets a² and 65 are shaped on arcs of circles to correspond with the shape of the

page_text: cam K, and the socket a³ is so placed in the case A' as to be exactly in line with
the socket 65 in the idler D', when the bolt is shot and the door locked, and the
pin a and cam K₁ are so positioned that when the cylinder A' is turned to unlock
the door, in the direction of the arrow, Fig. 25, the flat side k of the cam K' will
be pressed against the pin a³. There is a spring not shown, but arranged in a
manner as will be well understood by lock makers, which tends to turn this cam K¹
up into the socket a².
+
The operation is as follows: Suppose the door is closing, the cylinder A³ being
locked by the pins 7, r, and that the idler D¹ is inclined to the right, as in Fig 15,
and that consequently the socket 65 in said idler D' is to the right of the cam K.
Said cam K will therefore be in the position indicated by the dotted lines in
Fig. 26, wherein its round side k cannot turn up into the socket, a², in the case A¹
because its straight side, will be pressing against the rim.: 41 of the idler D'.
Now the door is closed, the strike lever projecting the bolt and inclining the
idler D' to the left, so that its socket 65 is in line with the cam K¹, it being
understood that the idler D' turned freely because the curved slot 52 in said idler
passed freely along-by the pin 35. Now the cam K', will be immediately turned
up into the socket 65 in the idler by reason of the cam spring, and will prevent
the pushing back of the bolt. At the same time also the cam K', enters the
socket a² in the case A¹. The pin 35 is now at the right end of the slot 52,
(Fig. 26) and the door is locked. To unlock it, the proper key is inserted in the
key cylinder, B¹, whereby the pins y, r, are lifted so that the cylinder A³ can
revolve. Now by turning the key the said cylinder is revolved in the direction of
the arrow, Fig. 25, and thereby the straight side k¹ of the cam K¹ is pressed
against the pin a', whereby the cam K' is revolved so that its round side k passes
down out of the socket a³, and also of course down out of the socket 65 in the
idler D. As the cylinder revolves the pin 35 carries the idler D' in the same
direction until further motion is stopped by the said pin 35 coming against the
right end of the slot 55 within the plate, A. The idler is now inclined to the
right, and the bolt is drawn back so that the door is opened and the strike lever
projects to be ready for another closing of the door as has been herein before
described. But as will be understood by those acquainted with pin locks, the key
cannot be withdrawn until the cylinder A³ has been turned back to its first position.
Consequently the key is so turned backward thereby revolving the cylinder A' to
its first position, the pin 35 ineantime returning freely through the slots 52 and 55
without moving the idler D¹. The key is now taken out of the lock and all is
ready for a second operation.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that what I
claim is,
1. In cylinder locks, and in combination with a bolt and a strike lever, an idler
pivoted to move independently of the cylinder, and devices for connecting
the idler with the cylinder, so that the idler may be moved by the cylinder.
2. The combination, in cylinder locks, of shiftable tumblers, a shiftable locking-
bar actuated by the tumblers, and an idler pivoted so as to move independently of
the cylinder and having a socket adapted to be engaged by a spring cam on the
locking-bar.
3. The combination in cylinder locks of a locking-bar actuated by tumblers and
having a can adapted to enter a socket in the fixed case of the lock, and also
having a spring actuated cam, to enter a socket in an idler that is pivoted to move
independently of the cylinder.
4. The combination of a lock cylinder carrying a shiftable cam and an
idler pivoted to move independently of the cylinder and having a socket to be
engaged by the cam..
5. The combination in a lock of a lock cylinder, a bolt, a strike lever, an idler

page_text: connected with the bolt and the strike lever and pivoted to move independently
of the lock cylinder, and devices for connecting the idler with the lock
cylinder.
6. In locks a locking-bar adapted to be actuated by tumblers, a spring cam
pivoted on the locking-bar and a shoulder on the locking-bar to engage the cam, as
.described.
7. The combination in a lock of a cylinder and an idler adapted to move
independently of the cylinder, and devices for connecting the said idler with said
cylinder, so that the cylinder can move the idler.
8. The combination in a lock of a shiftable locking-bar and tumblers each
having a projection adapted to shift said locking-bar and also an auxiliary projec-
tion adapted to prevent moving said locking-bar.
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.
COL
CORTAT TO Con
H. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.