U.S. patent number 3,667,262 [Application Number 05/105,359] was granted by the patent office on 1972-06-06 for key operated lock.
Invention is credited to Lewis J. Hill.
United States Patent |
3,667,262 |
Hill |
June 6, 1972 |
KEY OPERATED LOCK
Abstract
A lock including a body having a cylindrical bore therethrough
in which a plug is rotatably mounted. Apertures in the body
slidably receive drivers. The drivers are aligned, in one position
of the lock, with tumbler assemblies movably mounted in the plug.
The tumbler assemblies extend into a key slot in the plug, and
insertion of a key in this slot biases the several tumbler
assemblies to a lock-opening position in which the tumbler
assemblies contact the drivers along a shear line lying in the
interface between the plug and the body. The tumbler assemblies are
adjustable in their dimensions by the use of a change key so that
they may be altered to permit a new key to be made operative for
opening the lock. One part of each tumbler assembly carries a
projecting flange which projects through a radial slot in the plug
into one of a plurality of L-shaped slots formed in a master key
insert assembly. The master key insert assembly is positioned in a
slot in the plug which extends substantially parallel to the key
slot. The master key insert assembly includes an insert plate
having a plurality of the described L-shaped slots formed therein
which slidably accommodate L-shaped pins. One leg of each L-shaped
pin projects into the key slot in a position for cooperation with
the milled surface of a master key, so that when a master key
correlated to the particular master key insert assembly in use is
placed in the key slot, the L-shaped pins are biased by the milled
surface of the master key to a lock-opening position. The second
end of each of the L-shaped pins bears against the flange carried
by one portion of each tumbler assembly so that displacement of the
L-shaped pins by the master key moves the tumbler assemblies to a
lock-opening position. The master key insert assembly is slidably
disposed in a slot formed in the plug, and is retained in the slot
by cooperating retainer pins slidably positioned in the plug and in
the master key insert plate. A removal tool passageway is provided
in the insert plate in alignment with one end of the retainer pin
slidably mounted in the insert plate, so that a removal tool may be
used to bias this pin to a position in which the retainer pin in
the insert plate meets the retainer pin slidably mounted in the
plug along a shear line such that the master key insert assembly
may be slidably removed from the plug. After removal of the master
key insert assembly in the manner described, a new master key
insert may be slidably inserted in the plug so that a new master
key must be utilized to open the lock.
Inventors: |
Hill; Lewis J. (Oklahoma City,
OK) |
Family
ID: |
22305363 |
Appl.
No.: |
05/105,359 |
Filed: |
January 11, 1971 |
Current U.S.
Class: |
70/384; 70/341;
70/375; 70/493 |
Current CPC
Class: |
E05B
27/00 (20130101); Y10T 70/7469 (20150401); Y10T
70/7684 (20150401); E05B 27/0053 (20130101); Y10T
70/774 (20150401); Y10T 70/7605 (20150401) |
Current International
Class: |
E05B
27/00 (20060101); E05b 027/02 (); E05b
035/10 () |
Field of
Search: |
;70/384,383,382,340,341,337,338,375,364A,376-378 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wolfe; Robert L.
Claims
What is claimed is:
1. A key operated lock comprising:
a body having a circularly cross-sectioned bore therein;
a plug rotatably mounted in the bore and having a main key slot, a
change key slot and a master key insert assembly slot formed
therein and extending substantially parallel to the axis of
rotation of the plug in the body;
drivers movably mounted in the body for radial movement relative to
the bore in the body, and for movement partially into the bore in
the body;
tumbler assemblies movably mounted in the plug for radial movement
relative to the bore in the body and movable to a position
projecting from the plug, said tumbler assemblies and drivers
contacting each other in one position of said plug in relation to
said body, said tumbler assemblies each including a plurality of
releasably engaged parts movable relative to each other upon
disengagement to change the overall dimension of each of the
tumbler assemblies;
means for disengaging the relatively movable parts of each tumbler
assembly from each other upon insertion of a change key in the
change key slot in said plug and rotation of said plug to a
predetermined position within said body;
a master key insert assembly slidably positioned in said insert
assembly slot, said insert assembly comprising:
a supporting plate; and
a plurality of pins movably mounted on said supporting plate and
positioned for cooperation with a master key inserted in said main
key slot;
means releasably retaining said master key insert assembly in said
insert assembly slot; and
means secured to said tumbler assemblies and extending into contact
with said pins for imparting movement to said tumbler assemblies
when said pins are moved on said supporting plate by cooperation
with a master key.
2. A key operated lock as defined in claim 1 wherein
said supporting plate is further characterized in having a
plurality of slots therein;
and wherein said pins are each L-shaped in configuration and have
one end projecting into said main key slot, and further have a
second end contacting said means secured to said tumbler
assemblies.
3. A key operated lock as defined in claim 1 wherein said means
releasably retaining said master key insert assembly in said insert
assembly slot comprises cooperating retainer pins movably mounted
in said plug and said master key insert assembly.
4. A key operated lock as defined in claim 1 wherein said retaining
means comprises a retainer pin movably mounted in said plug and
engageable in one position with said master key insert
assembly.
5. A key operated lock as defined in claim 1 wherein said means
secured to said tumbler assemblies comprises a flange secured to,
and projecting from, one of the relatively movable parts of each of
said tumbler assemblies, said one relatively movable part
contacting one of said drivers in said one position of the plug in
relation to said body.
6. A key operated lock as defined in claim 1 wherein each of said
tumbler assemblies comprises:
a hollow housing positioned for contacting one of said drivers when
said plug is in said one position;
an extensible member movably mounted in said hollow housing for
adjusting the overall length of the tumbler assembly, and having a
portion projecting into the main key slot for cooperation with a
key inserted therein; and
a locking pin releasably engaging said extensible member with said
cap to prevent relative movement therebetween and to selectively
fix the length of the tumbler assembly, a portion of said locking
pin projecting into said change key slot.
7. A key operated lock as defined in claim 6 wherein said means for
disengaging the relatively movable parts of each tumbler assembly
from each other comprises a cam plate contacting the locking pin of
each tumbler assembly and movably mounted in a slot in said plug,
each of said cam plates having a cam surface projecting into
contact with the wall of the bore in said body, and each of said
cam plates having said cam surface positioned for contacting one of
said drivers to permit radial displacement of said locking pins and
cam plates upon isertion of said change key and rotation of said
plug.
8. A key operated lock as defined in claim 1 wherein said
supporting plate is further characterized in having a removal tool
bore extending thereinto, and a retainer pin aperture extending
thereinto and intersecting said removal tool bore, said retainer
pin aperture having an opening adjacent said plug;
and wherein said means releasably retaining said master key insert
assembly in said insert assembly slot comprises:
a first retainer pin movably positioned in said retainer pin
aperture and projecting into said removal tool bore; and
a second retainer pin movably positioned in said plug and
positioned for movement of a portion thereof into and out of said
retainer pin aperture for cooperation with said first retainer
pin.
9. A key operated lock as defined in claim 2 wherein said means
releasably retaining said master key insert assembly in said insert
assembly slot comprises cooperating retainer pin movably mounted in
said plug and said master key insert assembly.
10. A key operated lock as defined in claim 2 wherein said means
secured to said tumbler assemblies comprises a flange secured to
one of the relatively movable parts of each one of said tumbler
assemblies and projecting therefrom into contact with one of said
L-shaped pins, said one relatively movable part contacting one of
said drivers in said one position of the plug in relation to said
body.
11. A key operated lock as defined in claim 10 wherein said means
releasably retaining said master key insert assembly in said insert
assembly slot comprises cooperating retainer pins movably mounted
in said plug and said master key insert assembly.
12. A key operated lock as defined in claim 10 wherein said
supporting plate is further characterized in having a removal tool
bore extending thereinto and a retainer pin aperture extending
thereinto and intersecting said removal tool bore, said retainer
pin aperture having an opening adjacent said plug, one of said
retainer pins being slidably mounted in said retainer pin aperture
and having a portion projecting into said removal tool bore.
13. A key operated lock comprising:
a cylindrical body having a cylindrical bore therethrough;
a cylindrical plug rotatably mounted in said body and having formed
therein a main key slot and a slot for receiving a master key
insert assembly;
drivers movably mounted in said body for radial movement in
relation to said cylindrical bore;
tumbler assemblies movably mounted in the plug for radial movement
relative to said cylindrical bore, said tumbler assemblies and
drivers contacting each other in one position of said plug in
relation to said body;
a master key insert assembly slidably positioned in said
second-mentioned slot in said plug, and including means movable
within said plug and contacting said tumbler assemblies for biasing
the tumbler assemblies to a lock opening position upon movement of
said means to a preselected position correlated to a specific
master key insertable in said main key slot, said means including
portions projecting into said main key slot for cooperation with
the milled edge of a master key.
14. A key operated lock as defined in claim 13 wherein each of said
tumbler assemblies is adjustable in its dimensions to respond to
different keys inserted into said main key slot in contact with
said tumbler assemblies.
Description
BACKGROUND OF THE INVENTION
1. Related Patent Applications
This patent application contains subject matter closely related to
the subject matter disclosed in my co-pending U.S. Pat. application
Ser. No. 11,668 filed Feb. 16, 1970, now U.S. Pat. No. 3,589,153
issued June 29, 1971 and entitled "Key Operated Lock."
2. Field of the Invention
This invention relates generally to improved key operated locks.
More particularly, but not by way of limitation, this invention
relates to an improved key operated lock incorporating mechanism
adapted to permit the lock to be easily and rapidly changed for
operation by different individual keys, and also to be changed so
that a selected master key can be utilized for opening a number of
such locks.
BRIEF DESCRIPTION OF THE PRIOR ART
In my U.S. Pat. No. 3,320,781 and in my co-pending U.S. Pat.
application, Ser. No. 11,668, filed Feb. 16, 1970, I depict and
describe locks which can be quickly and easily structurally altered
so that a different key can be used to operate such locks, and the
key previously operable for opening the lock will no longer do so.
In addition to the individual, regular usage keys adapted to open
the individual locks involved, and individually correlated to each
individual lock of this type, one of the lock structures shown in
my U.S. Pat. No. 3,320,781, contemplates a construction of such
locks which are susceptible to being opened by a master key, so
that a plurality of such locks, while being openable by individual
keys in the hands of certain classes of persons, can also all be
opened by one master key in the hands of selected custodians.
It is, of course, desirable to be able to change one or more locks
in a business establishment, or even in homes, so that the key
normally used for opening the lock is changed, and an old key which
has previously been operative to open the lock will no longer work,
but only a new key. The locks of the type here under discussion
have been characterized in being susceptible to having the tumblers
and plungers forming portions of the lock mechanism changed in
their operative status relative to each other without the necessity
of disassembling the lock, or removing it from the door in which it
is located.
In large business establishments such as motels, hotels, and chains
of department stores, a great many locks are frequently utilized
which are of the general type described. In most cases, it is
desirable to provide a master key which will unlock any one of
these locks in the event persons in possession of the regular keys
for unlocking the locks should leave the door in a locked status,
or in the event that it should be desirable to hurriedly open the
door which is locked by such locks without seeking out the
individual key for the respective lock.
With the provision of one or more master keys which are maintained
in the custody of a few selected personnel, the versatility in
utilization of this type of lock in a multi lock situation is
increased. Situations arise, however, from time to time, in which a
custodian of a master key leaves the employ of the organization
where the locks are utilized, and, through inadvertence or intent,
takes one of the master keys which will unlock any of the locks in
use of the type described, and will continue to unlock such locks
even though the dimensions of the tumblers in the locks may be
changed to accommodate new individual patron keys. The security of
the establishment is obviously compromised by the loss of master
keys in this manner, and it is therefore desirable to be able to
change the locks so that master keys which would previously
effectively unlock or open the locks can no longer be used, and new
master keys are required for this purpose. It is further desirable
that the ability to change the mechanism of the lock for the
purpose of accommodating a new master key be accomplished without
the necessity for removing the lock from the door or disassembling
the lock.
BRIEF DESCRIPTION OF THE PRESENT INVENTION
The present invention constitutes an improved key operated lock
which includes the change key features described in my U.S. Pat.
application, Ser. No. 11,668, but which further incorporates an
important improvement in that the lock mechanism can be changed to
permit different master keys to be utilized for the purpose of
opening the lock, regardless of the configuration of any individual
patron key which may be operative to open the lock at any time.
Broadly described, the lock of the present invention comprises a
body having a cylindrical bore formed therein, and having an
elongated plug rotatably mounted in this bore. At one end of the
cylindrical bore in the body, an indentation or recess is formed
radially in the body for the purpose of receiving a retainer pin
slidably carried in the plug. A plurality of drivers are movably
positioned in apertures which extend radially in the body and
communicate with the bore therethrough. A plurality of adjustable
tumbler assemblies are movably positioned in radially extending
openings in the plug, and are aligned for contact with the drivers
when the plug is rotated to a predetermined position within the
body.
The plug has an axially extending change key slot formed therein,
and extending parallel to the axis of the cylindrical bore when the
plug is mounted in the body, and a main key slot extending over the
length thereof and extending parallel to the change key slot. A
plurality of axially spaced, circumferentially extending slots
extend between the change key slot and the radially extending,
tumbler-accommodating openings in the plug and accommodate cam
plates movably mounted in the plug for cooperation with a change
key inserted in the change key slot. A plurality of axially spaced
flange-accommodating slots extend between the tumbler-accommodating
openings in the plug and a master key insert assembly slot in the
plug to permit flanges carried by each tumbler assembly to extend
into a position for cooperation with certain portions of the master
key insert assembly.
The improvement provided by the present invention is based
structurally upon the provision of the described flanges carried by
the tumbler assemblies and extending into a position for
cooperation with portions of the master key insert assembly, and in
the provision of the master key insert assembly which is slidably
mounted in the master key insert slot in the plug, and is
detachable from the plug by the use of an insert removal tool as
hereinafter described. The remaining portions of the lock,
including the construction of the tumblers, the locking pins
provided for adjustably interlocking the relatively movable parts
of each tumbler, and the cam plates utilized for permitting the
tumbler dimensions to be adjusted upon cooperation of the cam
plates with a change key, are all of a construction shown and
described in detail in my co-pending Pat. application, Ser. No.
11,668, and such patent application is incorporated herein by
reference.
The master key insert assembly which is slidably positioned in the
master key insert slot in the plug of the lock comprises a
supporting plate which has a plurality of L-shaped slots spaced
axially therealong. The supporting plate extends axially in the
plug with respect to the axis of the cylindrical bore formed in the
body of the lock. The L-shaped slots accommodate L-shaped pins,
each of which has one end projecting from the respective L-shaped
slot in which it is located into the main key slot formed in the
plug. These ends of the L-shaped pins are thus positioned for
cooperation with a master key inserted in the main key slot. The
other end of each L-shaped pin bears against one of the flanges, to
which reference has previously been made, carried by one of the
tumbler assemblies slidably mounted in one of the radially
extending openings in the plug. The cooperation between the
L-shaped pins and the flanges of the tumbler assemblies is such
that insertion of a master key in the main key slot effectively
biases the several L-shaped pins to a position such that the
flanges cooperating with these pins, and secured to the several
tumbler assemblies of the lock, are moved to a lock-opening
position. Movement of these flanges moves the tumbler assemblies to
a position to permit the plug to be freely rotated within the body,
and the lock to be opened.
At one end of the supporting plate of the master key insert
assembly, this plate carries a retainer pin passageway in which a
retainer pin is movably mounted. A removal tool bore is formed in
the supporting plate and intersects the retainer pin passageway at
a right angle. Aligned with the retainer pin aperture is a second
retainer pin passageway formed in the plug, and a second retainer
pin is slidably located in this passageway in the plug, and is
aligned with and cooperates with the retainer pin disposed in the
retainer pin passageway formed in the supporting plate. The
retainer pin passageway in the plug is also positioned in the plug
such that when the plug is rotated to a predetermined position,
this passageway is aligned with the recess or indentation formed in
the body for the accommodation of the retainer pin.
A master key insert removal tool is provided which may be inserted
in the removal tool bore, and when so inserted, will bias the
retainer pin in the supporting plate to a position such that the
retainer pin in the supporting plate contacts the retainer pin in
the plug along a shear line lying in the interface between the
supporting plate and the plug. Concurrently, the master key insert
removal tool is interlocked with the retainer pin in the supporting
plate so that, by pulling on the removal tool along a line
extending parallel to the axis of the bore through the body, the
master key insert assembly may be slidingly withdrawn from the plug
in which it is mounted.
After the master key insert assembly has been thus removed, it may
be replaced by a different master key insert in which the
dimensions of the several L-shaped pins carried thereby are
different from those of the master key insert assembly previously
in use, and are correlated to the milled surface of a new master
key. With the replacement of the master key insert assembly in the
manner described, the old master key previously possessing the
capability of opening the lock is no longer operative for this
purpose, and a new master key correlated to the new master key
insert must be utilized.
From the foregoing description of the invention, it will be
perceived that it is an object of the invention to provide an
improved key operated lock which includes simple and mechanically
strong mechanism which is susceptible to selective change in
relative dimensions so that regular individual keys used therein
may be quickly changed, and so that master keys provided for the
operation of such locks, regardless of the regular individual keys
which are employed for opening the locks, can also be quickly and
easily changed without the necessity for disassembling the locks or
removing them from the doors in which they are located.
A further object of the invention is to provide a key operated lock
which is characterized in having a long and trouble free operating
life, and in which lock the regular key and the master key useful
for operating the lock may be quickly rendered inoperative, and the
lock accommodated to trouble free response to selected new
individual and master keys.
Another object of the invention is to provide an improved key
operated lock in which both the regular key and the master key
responsive locking elements within the lock structure can be
selectively altered to accommodate new keys of both types quickly
and easily.
Additional objects and advantages of the invention will become
apparent from the following detailed description of the invention,
and from the accompanying drawings which illustrate the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end elevation view of a key operated lock constructed
in accordance with the present invention.
FIG. 2 is a sectional view taken along line 2--2 of FIG. 1.
FIG. 3 is a sectional view taken along line 3--3 of FIG. 2.
FIG. 4 is a sectional view taken along line 4--4 of FIG. 2.
FIG. 5 is a sectional view taken along line 5--5 of FIG. 1.
FIG. 6 is a sectional view taken along line 6--6 of FIG. 4.
FIG. 7 is a side elevational view of a removal tool used in
operating the key operated lock of the present invention.
DETAILED DESCRIPTION OF A PREFERRED
EMBODIMENT OF THE INVENTION
Referring initially to FIG. 1 of the drawings, the key operated
lock of the invention includes a body 12 which is illustrated as
being generally cylindrical in form and is sometimes referred to in
the trade as the "cylinder." The body 12 has a cylindrical bore 14
(see FIG. 3) extending therethrough and a plurality of apertures 16
which extend radially through one wall of the body 12 into the
cylindrical bore 14. An elongated plug 18, which is preferably
generally cylindrical in configuration, is rotatably mounted in the
cylindrical bore 14 in the body 12. On a planar end face of the
body 12 which is seen in the end elevation view of FIG. 1 of the
drawings, an index mark 20 is provided on the face of the body, and
an index mark 22 is provided on the face of the plug 18. The
purpose of the indices marks 20 and 22 will be described more fully
hereinafter.
As can be seen most clearly in FIGS. 2, 5 and 6, the body 12
includes a circumferential flange 24 which extends around one end
of the body. The purpose of the flange 24 is to abut the face of a
door or other member in which the lock is to be installed. The body
12 has an external thread 26 which is provided to secure the lock
in the door or other member where the lock is to be used. An
elongated, dove-tailed groove or slot 28 (see FIG. 3) extends from
one end of the body 12 to the flange 24 and is provided to
accommodate a plate 30 which, when placed in the slot 28, covers
the apertures 16 in the body.
A driver 32 is slidingly positioned in each of the apertures 16 in
the body 12. Each driver 32 is constantly urged toward the plug 18
by a spring 34 which has one of its ends disposed in a recess or
bore in the respective driver 32 and its opposite end abutting the
elongated plate 30.
The body 12 has a shallow counterbore 36 in the end thereof which
carries the flange 24, and this counterbore intersects the
cylindrical bore 14 in the body at a shoulder 38. The plug 18 is
provided at one of its ends with an annular flange 39 dimensioned
to rotatably fit within the counterbore 36 and abut against the
shoulder 38 when the plug 18 is inserted in the cylindrical bore 14
in the body 12. At the end of the plug 18 opposite the flange 39,
the plug has secured thereto in any suitable manner (such as by
screws or the like) a lock cam 46 which serves the dual purposes of
preventing the plug 18 from moving toward the forward end of the
lock within the body 12, and to actuate a lock bolt (not shown) in
a manner well understood in the art.
A main key slot 48 extends longitudinally through the plug 18 and
is suitably configured to accept a key for operating the lock. The
key used in the main key slot 48 may be an individual patron key
for everyday usage, or may be a master key with the function and
mode of use of the two keys being hereinafter described in greater
detail.
A plurality of apertures 52 extend radially in the plug 18 and have
one end in communication with the key slot 48. The apertures 52
open at the outer periphery of the plug 18 and are positioned to
register with the apertures 16 in the body 12 when the plug 18 is
in the position within the body shown in FIGS. 1 and 2. The
apertures 52, in the illustrated embodiment of the invention, are
each generally cylindrical in configuration and are each
dimensioned to receive a generally cylindrical tumbler assembly 56
(see FIGS. 2 and 3).
Each of the tumbler assemblies 56 includes a hollow cylindrical
housing 60 which is closed at one end thereof and slidingly
disposed within one of the cylindrical apertures 52 in the plug 18.
Slidingly disposed within the interior of the cylindrical housing
60 is an extensible member 64 which has an upper portion 65
carrying a plurality of spaced circumferential flanges 66, and a
lower portion 68 which, when installed in the lock 10, extends into
the main key slot 48 to a position for contacting a key inserted in
the slot as depicted in FIG. 2 and hereinafter described in greater
detail. A spring member 70 is provided between the closed end 62 of
the hollow cylindrical housing 60 and the upper portion 65 of the
extensible member 64 to constantly urge the extensible member away
from the closed end of the cylindrical housing and toward the main
key slot 48.
A hollow projection 72 extends outwardly from one side of the
hollow cylindrical housing 60 and is adapted to receive a portion
of a locking pin designated generally by reference numeral 74. The
locking pin is of T-shaped configuration and includes a projecting
flange portion 76, a barrel 78, and a tip 80 formed on the end of
the barrel which is opposite the flange portion 76 (see FIG. 3).
The barrel 78 of the locking pin 74 projects through a bore formed
in the hollow projection 72 which extends outwardly from one side
of the cylindrical housing 60. It will further be noted that the
tip 80 of the locking pin projects between the spaced,
circumferential ribs 66 of the upper portion 65 of the extensible
member 64. The locking pin thus functions to engage the hollow
cylindrical housing 60 of the tumbler assembly 56 with the
extensible member 64.
Each of the generally cylindrical apertures 52 formed in the plug
18 opens at one of its sides into a substantially semicircular slot
82 cut radially inwardly into the side of the plug 18 and of the
general configuration shown in FIG. 3. There is one of the slots 82
cut in the body of the plug 18 in correspondence to each one of the
apertures 52, with the series of longitudinally spaced slots 82 in
the plug registering with the series of radially extending,
longitudinally spaced apertures 52 formed therein. The series of
slots 82 cut in one side of the plug 18 are intersected by a
longitudinally extending slot 84 cut along a major portion of the
length of the plug and extending from the outer surface of the plug
in a radially inward direction. At its base, the longitudinally
extending slot 84 intersects a relatively small, axially extending
change key slot 86 which extends through the plug 18 in a direction
parallel to the slot 84 and extends radially inwardly therefrom.
This relationship is perhaps best illustrated in FIG. 3 of the
drawings where a change key 88 is depicted in position in the
change key slot 86, and the lower portion of the longitudinally
extending slot 84 is perceptible in full lines and its upper
portion in dashed lines.
A cam plate 90 is provided in a cooperating relationship with each
of the tumbler assemblies 56. The cam plate 90 has a flat surface
92 which bears against the flange 76 of the locking pin 74 and has
a rounded cam surface 94 on the opposite side of the cam plate from
the flat surface. One of the cam plates 94 is provided for contact
with each of the locking pins 74, and each cam plate is elongated
and relatively thin in configuration as can be seen in referring to
these elements in FIGS. 2 and 3.
Each of the cam plates 90 has locating pins 96 projecting from the
opposite sides thereof. The cam plates 90 are positioned in the
several semicircular slots 82 with the locating pins extending into
the longitudinal slot 84 in the plug 14 in the manner best
illustrated in FIG. 2. The cam surfaces 94 of the several cam
plates 90 will, in most positions of the plug 18 within the housing
12, bear against the cylindrical wall of the bore 14 in the
housing. In one position to which the plug 18 may be rotated,
however, the cam surfaces 94 of the several cam plates 90 are
aligned with the apertures 16 in the body 12 which receive the
drivers 32. This position of the cam plates is depicted in FIG. 3.
It will be noted that when the plug 18 is rotated to the position
shown in FIG. 3, the cam plates 90 may be moved radially outwardly,
as may the locking pins 74 with which these plates are in contact.
As will be subsequently explained, this status of the lock permits
the change key 88 to be utilized for biasing the locking pins 74 to
a disengaging status so that the extensible members 64 and hollow
cylindrical housings 60 may undergo movement relatively to each
other.
There is further provided in the cylindrical plug 18, a master key
insert assembly slot 100. This elongated slot 100 extends
substantially parallel to the main key slot 48 and is of generally
L-shaped cross-sectional configuration, with a portion of the
insert assembly slot intersecting the main key slot 48 as best
illustrated in FIGS. 1, 3 and 4.
Machined radially inwardly in the plug 18 are a plurality of flange
accommodating slots 102. The flange accommodating radial slots 102
are axially spaced along the plug 18 and establish open
communication between the cylindrical apertures 52 which receive
the several tumbler assemblies 56, and the L-shaped master key
insert assembly receiving slot 100. To further describe the
location of the radial accommodating slots 102, these slots are
circumferentially aligned with, and in the same plane as, the
tumbler assembly receiving apertures 52 and the circumferential
slots 82, previously described. Each of the flange accommodating
slots 102 receives a flange 104 which projects from the opposite
side of the cylindrical housing 60 from the side thereof from which
the hollow projection 72 extends (see FIGS. 3 and 5). Each of the
tumbler assemblies 56 carries one of the flanges 104, the number of
flanges 104 being in correspondence to the number of flange
accommodating slots 102 provided along the length of the plug 18,
and these flanges are responsive to the movement of certain
portions of a master key insert assembly as more fully hereinafter
described.
A master key insert assembly utilized in the lock of the present
invention is depicted in the drawings and designated generally be
reference numeral 106. The master key insert assembly 106 is
slidably positioned in the cylindrical plug 18 in the insert
assembly slot 100 so that, under certain conditions hereinafter
described, the insert assembly may be made to slide longitudinally
within the plug 18. The master key insert assembly 106 includes an
insert plate or supporting plate 108 which is generally of L-shaped
configuration in conformation to the geometry of the insert
assembly receiving slot 100.
The supporting plate 108 has a solid end portion which is disposed
adjacent the flanged end portion of the plug 18 when the insert
assembly is disposed in the insert assembly slot 100. A small
removal tool aperture or bore 110 is formed in this portion of the
supporting plate 108 for the purpose of receiving a removal tool as
hereinafter described. The removal tool bore 110 extends axially in
the supporting plate 108 for a short distance as best depicted in
FIG. 6. A radially extending retainer pin passageway 112 extends
substantially normal to the removal tool bore 110, as best shown in
FIGS. 4 and 6 of the drawings, and slidingly receives a retainer
pin 114.
It will be noted that one end of the retainer pin 114 projects into
the removal tool bore 110. The opposite end of the retainer pin 114
bears against a cooperating retainer pin designated generally be
reference numeral 116. The cooperating retainer pin 116 is
slidingly positioned within a radial passageway 118 formed in the
cylindrical plug 18 in a position of alignment with the retainer
pin passageway 112 in the supporting plate 108. The retainer pin
passageway 118 is partially closed (crimped inwardly) at its end
adjacent the supporting plate 108 to form a stop or abutment
against which a collar 120 carried on the cooperating retainer pin
116 bears in one position of this pin. The passageway 118 is
configured so as to include a relatively large diameter bore
portion 118a in which the collar 120 may slidingly reciprocate, and
a relatively small diameter counterbore portion 118b. A stem
portion 122 of the cooperating retainer pin has a portion thereof
surrounded by a helical spring 124 and a portion thereof which
projects into the relatively small diameter counterbore portion
118b of the passageway 118. The retainer pin passageway 118 formed
in the cylindrical plug 18 is positioned so that, when the plug is
rotated within the body 12 to a position illustrated in FIG. 4, the
retainer pin 116 is aligned with a small recess 126 formed in the
internal wall of the body 12 which defines the cylindrical bore 14
extending therethrough. From the description of the construction,
configuration and relative location of the retainer pins 114 and
116, it will be perceived that each may move axially within the
respective passageways 112 and 118 so that a portion of the small
diameter stem portion 122 of the retainer pin 116 will extend into
the recess 126 formed in the body 12, and the retainer pin 114 will
meet the retainer pin 116 along a line which lies in the same plane
as the line of contact between the supporting plate 108 of the
insert assembly 106 and the cylindrical plug 18.
In the L-shaped supporting plate 108, the master key insert
assembly 106 further includes a plurality of L-shaped slots 130
formed in the supporting plate and spaced axially along its length.
A guide bar 132 (see FIGS. 3 and 5) cooperates with the supporting
plate 108 in retaining in the several L-shaped slots 130 formed in
the supporting plate, a plurality of L-shaped pins 134. Each of the
L-shaped slots 130 is oversized in relation to the L-shaped pin 134
located therein so that each L-shaped pin may slide axially within
its respective L-shaped slot--that is, each L-shaped pin may move
in a direction which is coaxial with respect to the relatively
longer of the two legs of the pin. One of the ends of each L-shaped
pin 134 projects into the main key slot 48, as best illustrated in
FIGS. 3 and 4, and the other end of each L-shaped pin is located
adjacent one of the flanges 104 carried by each tumbler assembly 56
as hereinbefore described. This relationship is shown in FIGS. 3
and 5. The length of the longest of the two legs of each of the
L-shaped pins 134 varies from one of these pins to the next, with
the lengths of these legs of the pins being correlated to the
milled surface of a master key. Due to this correlation, when a
master key is inserted in the main key slot 48, the L-shaped pins
134 are biased by contact with the milled, key engaging surface of
the master key to a position such that all of the ends of the
several L-shaped pins which contact the flanges 104 are aligned in
a single plane within the cylindrical plug 18. The function of the
L-shaped pins 134 will become more apparent when the operation of
the lock is subsequently described.
Several types of keys and a removal tool are used in conjunction
with the lock structure which has been described. Thus, an
individual patron key which is milled to unlock only a specific
individual lock of the type under discussion is utilized in the
normal utilization and operation of the lock, and this type of key
is depicted in position in FIGS. 1-4 of the drawings, and is
designated by reference numeral 150. A change key 88, utilized for
changing the dimensions of the tumbler assemblies 56 of the lock
mechanism so that these assemblies are responsive to a new and
different individual patron key, is provided for insertion in the
change key slot 86 and a change key of this type is illustrated
sectionally in FIG. 3. It is also fully illustrated in my
co-pending application, Ser. No. 11,668 filed Feb. 16, 1970.
Additionally, a master key which will function to open a number of
locks of the type described, despite their individual respon
responsiveness to individually operative patron keys, is also
utilized in the main key slot 48, and a master key of the type
described is depicted in dashed lines in FIG. 5, and is designated
by reference numeral 154. Finally, a removal tool is used with the
lock of the present invention for the purpose of removing from the
plug 18, the master key insert assembly 106. The removal tool is
shown in FIG. 7 and is designated generally by reference numeral
156. The removal tool 156 includes an end portion 158 adapted for
insertion in the removal tool bore 110, hereinbefore described, and
this end portion is provided with a tapered point and with a recess
160 spaced from the tapered point and adapted to receive one end of
the retainer pin 114 for a purpose hereinafter described.
OPERATION
In some of its functions and in certain modes of operation, the key
operated lock of the present invention corresponds closely to the
function and modes of operation which characterize the key operated
lock described in my co-pending application, Ser. No. 11,668, filed
Feb. 16, 1970, and entitled "Key Operated Lock." For the sake of
brevity at some points in the following discussion, it may
therefore be deemed expedient to make reference to the cited
co-pending application, as well as to my U.S. Pat. No. 3,320,781,
which is also directed to a change key lock generally similar to
that which is here under discussion.
The general operation of lock structures which include cooperating
drivers and tumbler assemblies of the type described is generally
well understood in the art. Locks of this type may be opened at
such time as the drivers 32 and the tumbler assemblies 56 cooperate
to permit the cylindrical plug 18 to be rotated within the body 12.
Such rotation of the plug 18 causes the lock cam 46 to be moved
against a lock bolt so as to release the door from its surrounding
frame and permit the door to be opened.
The nomenclature "change key lock" which is sometimes applied to
locks of the type here under discussion is derived from the
capability of the locks to be changed in their internal mechanism
so that a key which has previously been effective for unlocking the
lock will no longer perform this function, but rather, a new key
must be used for this purpose. In order to accomplish changing of
the keys in the manner described, the overall dimensions of the
tumbler assemblies 56 are changed so that these tumbler assemblies
will no longer cooperate with the milled surface of an individual
patron key 150 (previously operative to unlock the lock) in such a
way that unlocking can be accomplished, but rather, will be
accommodated, by virtue of the changed dimensions, to a new and
different key, having a different milled surface which is
correlated to the particular tumbler dimensions attained after the
change is effected.
In order to accomplish the described change in the dimension of the
tumbler assemblies 56, the old individual key, which is to be
rendered inoperative, is first inserted in the key slot 48 in the
cylindrical plug 18 in the manner depicted in FIGS. 1 and 2 (where
the key 150 represents the old individual patron key which it is
desired to render inoperative). Upon insertion of this key 150, the
overall dimensions of the tumbler assemblies, which are fixed by
the particular interlocking position of the tip 80 of the locking
pins 74 with the ribs 66 of the extensible members 65, are such
that the closed upper ends 62 of the cylindrical housings 60 are
positioned in alignment along a meeting line in contact with the
drivers 32. This meeting line coincides with the shear line between
the outer periphery of the cylindrical plug 18 and the wall
defining the bore through the body 12. With the drivers 32 and
tumbler assemblies 56 in this position relative to each other, the
plug 18 can then rotate within the cylindrical bore 14 in the body
12.
For the purpose of opening the lock, such rotation of the plug 18
is accomplished, and the lock cam 46 then performs its function of
biasing a lock bolt to an unlatching or unlocking position. Such
rotation of the plug 18 also must be effected in order to
accomplish the dimensional change in the several tumbler assemblies
56 which is necessary in order to make the lock mechanism
responsive to a new individual patron key and render the old key
inoperative. For this purpose, the plug 18 is rotated in a
clockwise direction, as viewed in FIG. 1, until the indicia mark 22
carried on the plug is aligned with the indicia mark 20 carried on
the body 12. It will be perceived that this amounts to a rotation
through 90.degree.. At this time, the plug 18 is in the position
relative to the body 12 shown in FIGS. 3 and 4. When the plug 18 is
in this position with the individual key 150 located therein, the
cam plates 90 are positioned in alignment with the apertures 16
which carry the drivers 32. Thus, the cam surfaces 94 of the cam
plates 90 bear against the inner ends of the drivers 32, and the
drivers may thus be biased outwardly in their respective apertures
16 against the force resiliently exerted by the springs 34.
With the lock in the status described, a change key 88 of the type
shown in my co-pending Pat. application, Ser. No. 11,668 is
inserted in the change key slot 86 and then comes to occupy the
position with respect to the locking pins 74 and cam plates 90
which is illustrated in FIG. 3 of the drawings. The change key 88,
when inserted in this manner, effectively biases the several
locking pins 74 outwardly with respect to the hollow projections
72. This movement of the locking pins 74 is possible because the
cam plates 90 are, at this time, free to move radially outwardly
against the drivers 32 which can move outwardly in their respective
apertures 16. There is thus effected a disengagement of the tips 80
of the several locking pins 74 from the extensible members 64
forming portions of the tumbler assemblies 56. The extensible
members 64 thus become free to move relative to the hollow
cylindrical housings 60 of the tumbler assemblies. It will be seen,
of course, that the hollow cylindrical housings 60 of the tumbler
assemblies 56 are immovable at this time due to the abutment of the
closed ends 62 thereof against the wall defining the bore 14 in the
body 12.
At this time, the individual patron key 150 may be removed from the
main key slot 48. This permits the extensible members 64 forming a
portion of each of the tumbler assemblies 56 to be biased by the
respective springs 70 to a position where the tapered face of each
extensible member adjacent the key slot 48 bears against a shoulder
formed within the plug 18. At this point, the movement of the
respective extensible member 64 is arrested. With the change key 88
remaining in position, a new individual patron key is then inserted
in the key slot 48. This effectively biases the extensible members
64 to new positions which are determined by the geometric
configuration of the milled edge of the new key placed in the key
slot 48. It also changes the relative positions of the several tips
80 on the locking pins 74 with respect to the ribs 66 formed around
the shanks of the extensible members 64.
After the new key has been inserted, the change key 88 is removed
from the change key slot 86. This permits the locking pins 74 to
respond to the bias of the springs 34 exerted through the drivers
32 and the cam plates 90, and to return to their position of
engagement with the extensible members 66 by extension of the tips
80 between adjacent pairs of the spaced ribs 66. It will be
perceived that the effect of the actions described is to readjust
the overall lengthwise dimension of the several tumbler assemblies
56 so that they are correlated to a new individual key, and this
new key, when inserted in the key slot 48, will result in the
cylindrical housings 60 of the several tumbler assemblies 56 being
biased to the shear line necessary to open the lock as previously
described. The plug 18 may then be rotated in a counterclockwise
direction as viewed in FIG. 1 to return it to its original locked
status, and the new individual patron key may then be removed. This
procedure of changing out the individual keys effective to open the
lock is described in detail in my co-pending Pat. application, Ser.
No. 11,668.
It is often desirable, where a single establishment has in use a
number of locks of the type described, to be able to open all of
these locks with a single master key. In order to accomplish this,
a master key 154 is inserted in the main key slot 48 instead of the
individual patron key. Insertion of the master key 154 in this slot
results in a milled edge of the master key passing beneath, and
biasing to certain predetermined positions, the L-shaped pins 134
carried by the master key insert assembly 106.
The action of the master key 154 in this respect may be perceived
in referring to FIGS. 4 and 5. Here it will be noted that the
milled edge of the master key 154 has passed beneath and, in
effect, wedged upwardly, the several L-shaped pins 134 by contact
of this milled edge with the end portion of the L-shaped pins which
projects into the main key slot 48. The dimensions of the several
L-shaped pins along the longest leg thereof will vary as between
the several pins, with such variation in dimension being correlated
to the variation in depth of the concave depressions forming the
geometric contour of the milled edge of the master key. The
correlation is such that, when the proper master key is inserted in
the main key slot 48, the upper ends of all of the L-shaped pins
134 (that is, the ends which are in contact with the flanges 104
secured to the tumbler assemblies 56) will be aligned along a
single line extending parallel to the axis of the cylindrical bore
14 through the body 12. Alignment of these ends of the L-shaped
pins 134 effectively biases all of the flanges 104 into alignment
with each other, and since these flanges are rigidly secured to the
hollow cylindrical housings 60 of the tumbler assemblies 56, the
result is that these housings are also all biased into alignment.
The alignment of the hollow cylindrical housings 60 of the tumbler
assemblies 56 is such that the closed ends 62 of these housings are
aligned along the shear line between the plug 18 and the body 12.
Thus, the condition is satisfied for free rotation of the plug 18
within the body 12, and the lock may be opened as a result of the
use of the proper master key.
As has been previously remarked, there may be occasions when one or
more of the master keys in use are lost, and the security of the
system of locks openable by the master key is therefore
compromised. In this event, it is desirable to change the lock
mechanisms so that the mechanisms are responsive to a different
master key. The lock of the present invention permits this to be
accomplished without removal of the bodies or housings of the locks
from the doors in which they are located.
The process of changing the mechanism to receive a different master
key is effected by initially removing from the plug 18, the master
key insert assembly 106. This assembly is removed from the insert
assembly receiving slot 100 in which it is located by first
inserting in the removal tool bore 110, the tapered end of the
removal tool 156 shown in FIG. 7. As the end portion 158 of the
removal tool 156 is pushed into the bore 110, the tapered point of
this tool passes under, and wedges upwardly, the retainer pin 114
slidably mounted in the retainer pin aperture 112. As the retainer
pin 114 is thus moved upwardly in the slot 114, it forces the
cooperating retainer pin 116 carried in the retainer pin passageway
118 outwardly in this passageway against the bias of the spring
124. The radially outer end of the retainer pin 116 at this time
extends into the recess 126 in the body 12.
Continued movement of the end portion 158 of the removal tool 156
into the removal tool slot 110 eventually brings the recess or
notch 160 formed in the removal tool into alignment with the
retainer pin 114. The retainer pin 114 then snaps into the recess
160 and is thus permitted to move to a position such that the
retainer pin 114 and the retainer pin 116 meet in the plane
containing the abutting surfaces of the supporting plate 108 and
plug 18. In this position, neither of the retainer pins 114 or 116
offer obstruction to the sliding movement of the supporting plate
108 in the slot 100. The entire master key insert assembly 106 may
thus be pulled outwardly to disengage it from the plug 18. The
outward movement of the master key insert assembly 106 is
facilitated by the engagement of the retainer pin 114 with the
recess 160 in the removal tool 156.
Once the master key insert assembly 106 has been pulled out of the
plug 118, the removal tool 156 may be disengaged from the insert
assembly 106 by rotating the removal tool through 90.degree. C, or
sufficiently to disengage the recess 160 from the end of the
retainer pin 114. The removal tool may, in this manner, be
disengaged or freed from the master key insert assembly 106. A new
master key insert assembly 106 which is constructed to respond to a
different master key is then positioned in the master key insert
assembly slot 100 in the plug 18. To accomplish this, the insert
assembly 106 is then pushed into the insert assembly slot 100. A
tapered end on the supporting plate 108 allows the insert assembly
106 to wedge the retainer pin 116 outwardly, so that one end
thereof projects into the recess 126 formed in the body 12. The
inner end of this retainer pin will then come to ride along the
upper surface of the L-shaped supporting plate 108 until the insert
assembly is fully seated, at which time the retainer pin 116 will
be aligned with the retainer pin 114, and the inner end thereof
will snap into the retainer pin aperture 112.
It will be understood that the new master key insert assembly 106
which has been positioned within the plug 18 in the manner
described contains L-shaped pins 134 which are differently
dimensioned than those forming a portion of the master key insert
assembly previously in use. The difference in the dimensions of the
L-shaped pins 134 on the new master key insert assembly 106, as
compared to the L-shaped pins previously in use is due to the
necessity to correlate the dimensions of these pins to the
different configuration of the new master key which is to be
effective for opening the locks. Thus, when the new master key,
having a differently configured milled edge, is inserted in the
main key slot 48 after changing out the master key insert assembly
106, the L-shaped pins of the new insert assembly will bear against
the milled edge of the new master key in such way that the upper
ends of the L-shaped pins 134 which contact the flanges 104 will be
brought into alignment along a line which is effective to permit
the lock to be unlocked.
Although certain preferred embodiments of the invention have been
herein described in order to illustrate the principles of the
invention, it will be understood that various changes and
innovations in structure can be effected without departure from
these principles. Changes and innovations of this type are
therefore deemed to be circumscribed by the spirit and scope of the
invention except as the same may be limited by the appended claims
or reasonable equivalents thereof.
* * * * *