U.S. patent number 3,595,043 [Application Number 04/797,863] was granted by the patent office on 1971-07-27 for keylock mechanism.
Invention is credited to Daniel A. Williams.
United States Patent |
3,595,043 |
Williams |
July 27, 1971 |
KEYLOCK MECHANISM
Abstract
A keylock mechanism is disclosed herein having a housing holding
an outer cylinder and rotatably supporting a middle cylinder which,
in turn, supports an inner cylinder rotatably mounted on a plug of
a ratchet mechanism, all of which are in coaxial relationship. A
plurality of tumbler chambers are formed in the outer cylinder
resiliently holding a portion of a plurality of pins of varying
lengths adapted to be combined to lock or release the cylinders and
plug. The middle cylinder, inner cylinder and the plug are formed
with openings adapted to be selectively aligned with selected ones
of the chambers so as to slidably receive the set of combined pins
carried in said selected chamber. A ratchet mechanism connected
between the inner cylinder and the plug permits the openings
therein and in the middle and inner cylinders to be selectively
aligned with chamber openings in the outer cylinder so that a
multiplicity of pin tumbler combinations can be chosen. An
engineer's key is employed to rotate or set the middle and inner
cylinders and their associated openings with respect to the outer
cylinder chambers to change combinations and a guest or operative
key is employed to actuate the pin tumblers in each of the selected
chambers so as to rotate the inner cylinder and the plug to release
the lock.
Inventors: |
Williams; Daniel A. (Los
Angeles, CA) |
Family
ID: |
25171981 |
Appl.
No.: |
04/797,863 |
Filed: |
February 10, 1969 |
Current U.S.
Class: |
70/273;
70/493 |
Current CPC
Class: |
E05B
27/0053 (20130101); Y10T 70/704 (20150401); Y10T
70/7605 (20150401); E05B 17/042 (20130101); E05B
27/001 (20130101) |
Current International
Class: |
E05B
27/00 (20060101); E05B 17/04 (20060101); E05B
17/00 (20060101); E05b 025/00 () |
Field of
Search: |
;70/385,382,383,384,339--343,359,364R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Champion; Marvin A.
Assistant Examiner: Wolfe; Robert L.
Claims
What I claim is:
1. A lock mechanism adapted to be unlocked by a guest key and
changed in combination by an engineer's key comprising:
a housing holding an outer chamber having a central bore and a
plurality of closely fitting inner and middle cylinder segments,
each assembly of cylinder segments forming a plurality of radial
chambers in communication with said central bore;
a series of middle cylinder segments rotatably mounted in said bore
having a plurality of holes aligned with said radial chambers;
said series of inner cylinder segments rotatably mounted in coaxial
alignment with said middle cylinder and having a plurality of holes
aligned with said middle cylinder holes;
an elongated plug rotatably carried on and in coaxial relationship
with said inner cylinder segments having a keyway and a plurality
of holes aligned with said inner and middle cylinder holes;
a tumbler pin assembly resiliently carried in each of said radial
chambers and extending through respective aligned inner and middle
cylinder segments and plug holes extending into said plug
keyway;
means connecting between said inner and middle cylinder segments
and said plug for selectively aligning said holes in said cylinders
and said plug with respect to each other so that a multiplicity of
tumbler pin combinations can be chosen in response to insertion of
the engineer's key into said plug keyway; and
said tumbler pin assemblies being operative to permit rotation of
selected ones of said inner cylinder segments and said plug as a
unit to effect release of the lock in response to insertion of the
guest key into said plug keyway.
2. A lock mechanism adapted to be unlocked by a guest key and
changed in combination by an engineer's key comprising:
a housing holding an outer chamber having a central bore and a
plurality of radial chambers in communication with said central
bore;
a middle cylinder rotatably mounted in said bore having a plurality
of holes aligned with said radial chambers;
an inner cylinder rotatably mounted in and coaxial with said middle
cylinder having a plurality of holes aligned with said middle
cylinder holes;
an elongated plug rotatably carried on and in coaxial relationship
with said inner cylinder having a keyway and a plurality of holes
aligned with said inner cylinder holes;
a tumbler pin assembly resiliently carried in each of said radial
chambers and extending through respective aligned cylinder and plug
holes into said plug keyway;
means connecting between said inner cylinder and plug for
selectively aligning said holes in said cylinders and said plug
with respect to each other so that a multiplicity of tumbler pin
combinations can be chosen in response to insertion of the
engineer's key into said plug keyway;
said outer cylinder is fixedly secured to said housing and said
middle cylinder, said inner cylinder and said plug are all
coaxially disposed and adapted to rotate independently of each
other or selectively together as a unit as predetermined by the
individual dimensional length of each of said pins in each of said
assemblies;
said middle cylinder is segmented along its length to permit
separate rotation of each of said segments; and
gear means interconnected between said segments for selectively
rotating said segments upon insertion and rotation of the
engineerkey.
3. A lock mechanism adapted to be unlocked by a guest key and
changed in combination by an engineer's key comprising:
a housing holding an outer chamber having a central bore and a
plurality of radial chambers in communication with said central
bore;
a middle cylinder rotatably mounted in said bore having a plurality
of holes aligned with said radial chambers;
an inner cylinder rotatably mounted in and coaxial with said middle
cylinder having a plurality of holes aligned with said middle
cylinder holes;
an elongated plug rotatably carried on and in coaxial relationship
with said inner cylinder having a keyway and a plurality of holes
aligned with said inner cylinder holes;
a tumbler pin assembly resiliently carried in each of said radial
chambers and extending through respective aligned cylinder and plug
holes into said plug keyway;
each of said tumbler pin assemblies includes a plurality of
coaxially disposed pins;
means connecting between said inner cylinder and said plug for
selectively aligning said holes in said cylinders and said plug
with respect to each other so that a multiplicity of tumbler pin
combinations can be chosen in response to insertion of the
engineer's key into said plug keyway;
said tumbler pin assemblies being operative to permit rotation of
said inner cylinder and said plug as a unit to effect release of
the lock in response to insertion of the guest key into said plug
keyway;
said middle cylinder comprises a plurality of coaxial cylinder
segments adapted to rotate about said inner cylinder independently
of each other; and
means carried on said middle cylinder segments for selectively
rotating said middle cylinder segments with respect to each other
to effect alignment of selected ones of said tumbler pins in one of
said assemblies with said tumbler pins in another one of said
assemblies.
4. The invention as defined in claim 3 wherein said connecting
means comprises a ratchet mechanism having a pawl pivotally carried
on one end of said plug and a plurality of ratchet teeth carried on
one end of said inner cylinder.
5. The invention as defined in claim 3 wherein said rotating means
includes a 360.degree. ring gear fixed on selected ones of said
middle cylinder segments and a quarter gear fixed on selected ones
of said middle cylinder segments; and
a rotatable shaft mounted on said housing carrying pinion gears
meshed with each of said ring gears respectively, and selectively
meshed with certain ones of said quarter gears.
6. The invention as defined in claim 3 wherein
said pin tumbler assemblies each include a plurality of coaxially
disposed pins of varying lengths but having the same combined
dimensioned length; and
selected ones of said pins in each of said assemblies being adapted
to be combined with adjacent assemblies upon rotation of said
middle and inner cylinders to effect lock combination change.
7. The invention as defined in claim 3 including key registration
means carried on said housing adapted to releasably engage with a
cutout formed in said engineer's key or said guest key.
8. The invention as defined in claim 3 wherein
said outer cylinder is fixedly secured to said housing and said
middle cylinder, said inner cylinder and said plug are all
coaxially disposed and adapted to rotate independently of each
other or selectively together as a unit as predetermined by the
individual dimensional length of each of said pins in each of said
assemblies.
9. The invention as defined in claim 3 wherein
said middle cylinder is segmented along its length to permit
separate rotation of each of said segments; and
gear means interconnected between said segments for selectively
rotating said segments upon insertion and rotation of the
engineer's key.
10. The invention as defined in claim 2 wherein
said gear means includes a ring gear and a quarter gear carried on
selected ones of said middle cylinder segments; and
pinion gears rotatably carried on said housing meshed with said
ring gears and selectively meshed with said quarter gears so that
said ring gear carried by one segment and said quarter gear carried
by another segment are engaged simultaneously.
11. The invention as defined in claim 2 wherein
said inner cylinder is segmented along its length and each of its
segments are adapted to rotate independently.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to door locks and, in particular, to a novel
keylock mechanism subject to operation by an operative key to
selectively lock or unlock the mechanism and subject to change of
the lock combination by use of an engineer's key. The mechanism is
more appropriately one which finds considerable use in locks for
public accommodations where a key may frequently change hands.
2. Description of the Prior Art
A particular type of installation where special key features are
found advantageous resides in a hotel or motel where a key is given
out to a different occupant each time a room is rented. Many times
keys are not returned. Also, keys in the hands of casual occupants
can easily be duplicated for future unauthorized use.
There is an obvious need for a pin tumbler lock that is suitable
for door use in hotels, motels and other establishments in which it
is necessary to change the combination with some frequency.
Although these establishments have been employing combination locks
for many years, the number of combinations available for change in
each lock is very limited and it is difficult to change from one
combination to another. It is the conventional practice to employ
special tools and the skillful services of an expert to effect such
combination changes even when the lock mechanism provides for such
a change.
Conventionally, lock mechanisms have been developed for changing
combinations which require the use of a key made in two parts, the
two halves of which must be carefully and tediously maneuvered to
adjust the pins of the mechanism to the contours of a new key. This
procedure will obviously require the services of an expert and will
in itself consume considerably time. It is also possible to open or
release the lock mechanism by using conventional burglar's tools
such as picks or the like, so that the lock mechanism is neither
pick-proof or burglar-proof.
Examples of prior art lock mechanisms which permit changing of key
combinations are located in the disclosures of U.S. Letters Pat.
Nos. 1,561,223; 3,090,219 and 3,290,910. However, lock mechanisms
of these latter types are limited in the number of combination
changes which can be made and fall short of being burglar
proof.
SUMMARY OF THE INVENTION
Accordingly, the difficulties and problems encountered with
conventional lock mechanisms adapted to change combinations are
obviated by the present invention which provides a keylock
mechanism that is both pick-proof and burglar-proof. The keylock
mechanism requires no special training to effect the change of
combination and the multiplicity of combinations available are
vastly increased over the number of possible combinations available
by use of conventional locks. By employing an engineer's key which
may be inserted in the lock keyway, a pin tumbler combination
change may be effected in less than one second. A guest or
operative key may be employed in the same keyway for effecting
locking and unlocking procedures in accordance with the particular
combination selected by the engineer key.
In one form of the invention, a housing is provided for supporting
a stationary outer cylinder formed with a plurality of axial
chambers in communication with a central longitudinal opening. The
outer cylinder coaxially and rotatably supports, within the central
opening thereof, a middle cylinder, an inner cylinder and a plug
having longitudinal keyway. Each of the middle and inner cylinders
and the plug are formed with axial openings in alignment with each
of the axial chambers formed in the outer cylinder. A plurality of
pin tumblers are resiliently carried in each of the chambers and
biased through respectively aligned openings in the middle and
inner cylinder as well as in the plug so as to project into the
keyway.
When a guest key is inserted into the keyway, selected ones of the
pins in each chamber are aligned to provide a horizontal parting
line in coextension with the interface of the inner cylinder with
the middle cylinder whereby clockwise rotation of the key effects
rotation of the plug. The plug carries an extension projecting
beyond the housing adapted to actuate the door latch mechanism.
A combination change is effected in response to the presence of an
engineer key in the keyway which sets the tumbler pins in the
respective chambers so that only the parting line of the pins match
the interface between the middle cylinder and outer cylinder so
that rotation of the middle, and inner cylinders and the plug is
produced. A ratchet mechanism interconnects the inner cylinder with
the plug so that as the key is rotated clockwise, the first portion
of the middle and inner cylinders will rotate to select another pin
tumbler chamber. Second, third and fourth middle and inner cylinder
portions are sequentially rotated for each quarter turn of the
engineer key via a set of quarter or quadrant gears. The ratchet
mechanism is stepped according to the quarter turn sequence. A ring
gear and pinion gear arrangement cooperate with the quarter gears
to serve as a transfer mechanism for aligning selected pin tumbler
chambers with the holes or openings in the cylinders and plug to
effect a variety of combination changes.
Therefore, it is among the primary objects of the present invention
to provide a novel pin tumbler lock mechanism capable of effecting
a multiplicity of unlocking combinations.
Another object of the present invention is to provide a novel pin
tumbler lock mechanism adapted to be operated by a guest key and
adapted to selectively change the unlocking combination by an
engineer key.
Another object of the invention resides in providing a plurality of
coaxial cylinders adapted to be selectively rotated together or
separately so as to rearrange radial key cylinder assemblies to
place the selected assemblies in an operative location for
actuation by a guest key.
Still another object of the invention resides in providing a novel
keylock mechanism which is pick-proof and burglar-proof and is
operative in response to a guest key for actuation purposes while
being operative in response to an engineer's key for effecting
combination change of the lock mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention which are believed to be
novel are set forth with particularity in the appended claims. The
present invention, both as to its organization and manner of
operation, together with further objects and advantages thereof,
may best be understood by reference to the following description,
taken in connection with the accompanying drawings, in which:
FIG. 1 is a side elevational view of the novel key lock mechanism
of the present invention shown in a typical installation on a door
with a guest key in position for insertion therein;
FIG. 2 is a front elevational view of the installed keylock
mechanism as taken in the direction of arrows 2-2 of FIG. 1;
FIG. 3 is a longitudinal cross-sectional view of the keylock
mechanism illustrating the internal component parts thereof with a
guest key inserted in the keyway of the mechanism;
FIG. 4 is a transverse cross-sectional view of the keylock
mechanism as taken in the direction of arrows 4-4 of FIG. 3;
FIG. 5 is a transverse cross-sectional view of the keylock
mechanism as taken in the direction of arrows 5-5 of FIG. 3;
FIG. 5A is a side elevational view of an engineer's key of the
present invention;
FIG. 6 is an exploded view of a portion of two primary component
parts employed in the keylock mechanism;
FIG. 7 is a perspective view of the ratchet mechanism employed in
the keylock mechanism;
FIG. 8 is a fragmentary view of the ratchet mechanism mounted in
the intermediate barrel;
FIG. 9 is a sectional view of the four slotted keyways employed in
the keylock mechanism;
FIGS. 10--13 are transverse cross-sectional views of the keylock
mechanism shown in FIG. 3 as taken in the direction of the
respective numbered arrows thereof;
FIG. 14 is a front elevational view of a circular slide rule type
chart showing initial pin tumbler cylinder assembly relationships
for various combinations; and
FIG. 15 is a chart similar to the chart shown in FIG. 14 showing
pin tumbler relationships for various guest key combinations.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a lock mechanism, indicated in the general
direction of arrow 10, is illustrated as being mounted on a
conventional door 11 having a front panel 12. The lock mechanism is
shown in combination with a key 13 poised for insertion into the
mechanism for effecting the unlocking thereof. The key 13 includes
an elongated shank 14 which is, preferably for some applications,
cylindrical and which is provided with a plurality of cutouts or
bits 15. Each of the bits is cut to a predetermined depth and the
depths of all the bits are selectively cut so as to provide a
preselected code effective to unlock the mechanism. It is to be
understood that the key 13 may include a pair of bit rows disposed
on opposite sides of the shank 14 or, as illustrated, the shank may
include four or more individual rows of bits wherein each row is
located at an angle with respect to the adjacent rows equal to
360/n, where n is the base number of the permutation
P.sub.r.sup.n.
The lock mechanism includes a mechanism housing 16 incorporating a
pinion housing 17 which is formed with a plurality of threads 18
adapted to threadably receive a mounting nut 20. A frontpiece 21 is
carried on the forward end of the mechanism housing 16 and is
formed with an annular flange adapted to seat against the front of
the door panel 12 while the lock nut 20 holds the mechanism in
place when the nut is tightened against the back side of the panel
12.
Referring now to FIGS. 2 and 3, the mechanism housing 16, including
a backup plate 19, is provided with an internal cavity which is
occupied by an outer cylinder 22, a middle cylinder 23, an inner
cylinder 24, and a plug 25. One end of the plug 25 projects
outwardly from the housing plate 19 and is suitably connected to a
conventional latch mechanism (not shown) adapted to actuate a latch
upon rotation of the plug. The outer cylinder 22 is held stationary
by means of a setscrew 26 which suitably secures the outer cylinder
to the housing 16. The outer cylinder includes a plurality of axial
pin tumbler chambers, such as is indicated by numeral 27 wherein
each chamber is adapted to resiliently mount a portion of a tumbler
pin assembly comprising a plurality of pins of varying lengths
which are placed in end-to-end relationship so as to project out of
the chamber into aligned apertures or holes formed in the middle
and inner cylinders as well as in the plug 25. The chambers 27 are
arranged in rows corresponding to the number of bits on the key 13.
For example, if the key is provided with two bits, then an upper
and lower row of chambers and tumbler pin assemblies are provided.
In the event the key is provided with four bits, then four rows of
chambers are provided at a 90.degree. relationship corresponding to
the four bits of the key.
For clarification, a single chamber and tumbler pin assemblage will
be described. In chamber 27, for example, as seen in FIG. 4, four
pins are illustrated in alignment which are biased in the direction
of the plug 25 by means of an expansion spring 30 into a keyway of
the plug. The endmost pin "a" of the plurality is adapted to pass
through the plug 25 into communication with a selected cut in the
key. The plurality of pins commencing with pin "d" bearing against
spring 30 and extending to pin "a" adapted to enter the cutout of
the key bit may be represented by the letters "d," "c," "b" and
"a," respectively. When the guest key 13 is fully inserted into the
plug 25, pins "b" and "c" associated with each of the cylinder
assemblages are displaced a distance equal to the corresponding
cuts in the key and form a parting line in alignment with the
interface of the inner cylinder and the middle cylinder, so that
rotation of the inner cylinder with respect to the middle cylinder
can take place. Pins "a" lock the plug to the inner cylinder and
the pins "c" lock the middle cylinder to the outer cylinder.
Therefore, insertion of the guest key 13 effects rotation of the
plug and inner cylinder as a unit and, since rotation of the plug
25 actuates the latch mechanism, locking or unlocking of the latch
is thereby effected.
The "b" and "c" pins are contained mostly within the respective
chambers of the inner and middle cylinders and project partially
into the outer cylinder only when a key is inserted in the lock.
The "a" pins are contained in the plug at all times and only the
"b" pins normally extend into the chambers of the inner cylinder.
The "b" pins and "c" pins vary in length from chamber to chamber,
but their combined length is always the same and therefore constant
and exactly equals the combined length of the chambers of the inner
and middle cylinders.
In FIG. 4, the relationship of each of the aligned and radial
chamber assemblages carrying the respective lengths of combined
pins is illustrated. When the guest key is inserted in the keyway,
it can be seen that the "a" pins lock the plug to the inner
cylinder and that the "c" pins lock the middle cylinder to the
outer cylinder.
Referring now to FIGS. 3 and 5, the lock mechanism is provided with
a means for effecting combination change by rotating selected
chambers so as to carry a portion of the pins of each assembly
therewith from one set of chamber pin assemblages to another. This
is achieved by means of insertion of an engineer's key as
illustrated by key 31 in FIG. 5a. The engineer's key includes
cutouts or bits in a similar fashion to key 13 with the exception
that the depth of the cutouts are coded differently therefrom. The
lock mechanism includes a 360.degree. full round advance mechanism
which includes a spur gear 32 rotatably carried within the
respective outer cylinder chambers and which are attached to the
middle cylinder 23. In addition, selected ones of the cylinder
assemblages include a quarter or quadrant gear 33. The quadrant
gears are similarly secured to the middle cylinder 23. However, it
is to be noted that the middle cylinder 23 is segmented along its
length into four sections so that rotation of each section is
effected by rotation of a preceding middle cylinder section. By
this means, a type of advance or transfer mechanism is provided by
positioning various groups or assemblages of pins with respect to
one another and with respect to pins held by the other cylinder and
plug. The 360.degree. gears, as well as the quadrant gears, are
actuated by means of pinion gears 34--36 inclusive which are
rotatably carried on a pinion shaft 37 fixed in the pinion housing
17. It is to be noted that the middle cylinder segment, fourth
cylinder assembly, is not attached to nor carries a 360.degree.
full round advancement gear. It does, however, attach to a
90.degree. quadrant. The middle cylinder segment of the fourth
assembly, therefore, will rotate through 270.degree. or three pin
positions before the leading edge of the quadrant will engage the
number three advance pinion indicated by numeral 36. This pinion,
in turn, meshes with a 360.degree. gear that is attached to the
middle cylinder segment of cylinder assembly number three.
Now, as cylinder assembly number four is rotated into the fourth
pin position, the attached quadrant rotates pinion number three
which, in turn, rotates the full round gear attached to cylinder
assembly number three and advances this assembly one pin position.
The quadrant attached to assembly number three also is advanced one
position.
The quadrant attached to cylinder segment number four now
disengages from its pinion and is allowed to rotate through
270.degree. (three pin positions) before it will again engage the
pinion.
Bear in mind that the number three segment quadrant does not cause
the number two assembly to rotate until it has rotated through
270.degree. or three pin positions and has engaged advance pinion
number two. This pinion number two as indicated by numeral 35 will
now rotate the full round 360.degree. gear attached to cylinder
assembly number two and will rotate this assembly through one
position of 90.degree., advancing the attached quadrant to the next
succeeding position. It is important to note that one quadrant and
one full round gear attach to the same cylinder segment, except for
segment four which does not attach to a 360.degree. gear, and
segment one which does not attach to a quadrant.
A feature of the invention resides in the fact that a ratchet
mechanism interconnects the plug with the inner cylinder and is
indicated by a plurality of teeth 40 carried on the last segment of
the inner cylinder and a ratchet pawl 41 carried on the plug. This
ratchet mechanism is shown more clearly in FIGS. 8 and 9 with the
extreme end of the inner cylinder annularly notched to rotatably
ride on an annular flange 42 carried on a pawl mounting ring
43.
Referring now in detail to FIG. 6, the lock mechanism is shown in
an exploded view so that the component parts may be readily
identified and corelated with the longitudinal sectional view shown
in FIG. 3. The outer cylinder 22 includes a plurality of chambers
27 adapted to receive portions of tumbler pin assemblies
respectively. Alternate chambers, such as is indicated by numeral
45, are intended to receive a 360.degree. advancement gear 32. As
mentioned previously, the middle cylinder 23 is segmented along its
length and includes rear portion 23' which carries a quadrant gear
33. Other middle cylinder segments take the form of middle segment
23" which includes a 360.degree. advance ment gear 32 and a
quadrant gear 33 fixed on opposite sides of the segment. Each
segment of the middle cylinder includes holes or apertures 46
adapted to be placed in alignment with the respective chambers 27
of the outer cylinder while the 360.degree. advancement gear is
disposed within the respective chambers 45 and the quadrant gear 33
is similarly disposed in chambers 45. The inner cylinder 24 is
similarly segmented along its length which includes a segment 24'
which is repeated for each of the outer cylinder chambers 27, and
an end segment 24" which is provided with teeth 40 adapted to
operate with the ratchet pawl 41. All of the segments of the inner
cylinder include holes or apertures 47 adapted to be selectively
aligned with the apertures 46 and chambers 27. However, it is to be
noted that the plug 25 is not segmented and is a continuous length
with a plurality of holes 48 formed therein so as to be selectively
aligned with the chambers 27 and holes 46 and 47 respectively.
In FIG. 7, it can be seen that the plug 25 includes a keyway 50
adapted to insertably receive the shank of the key 13 or 31.
With reference to FIGS. 10--13 inclusive, it can be seen that the
combination of pin tumbler assemblies may be readily changed by
inserting the engineer's key into the keyway of plug 25, turning
the key in a clockwise direction for a quarter turn and then
returning the key, plug and pawl to the original upright position
and withdrawing the key from the keyway. When this procedure has
been completed, the lock cannot be opened until a new guest key has
been issued and inserted into the keyway. In these latter FIGURES,
FIG. 10 is a view of the first (front) cylinder and pin tumbler
assembly in each of the aligned cylinder and plug holes with the
chamber 27 associated with a radial set of assemblies. FIG. 11 is a
view of the second cylinder and tumbler assemblies and FIGS. 12 and
13 are similar views of the third and fourth (rear) cylinder and
tumbler assemblies.
Typical pin lengths are given in the following tables associated
with each of the FIGS. 10--13 inclusive and where all "c" pins are
preferably of the spool type.
---------------------------------------------------------------------------
FIGURE 10
Pin 1a=0.100" Pin 2a=0.100" Pin 1b=0.120" Pin 2b=0.100" Pin
1c=0.160" Pin 2c=0.180" Pin 1d=0.060" Pin 2d=0.060"
Pin 3a=0.100" Pin 4a=0.100" Pin 3b=0.080" Pin 4b=0.060" Pin
3c=0.200" Pin 4c=0.220" Pin 3d=0.060" Pin 4d=0.060"
---------------------------------------------------------------------------
FIGURE 11
Pin 5a=0.080" Pin 6a=0.080" Pin 5b=0.140" Pin 6b=0.120" Pin
5c=0.140" Pin 6c=0.160" Pin 5d=0.080" Pin 6d=0.080"
Pin 7a=0.080" Pin 8a=0.080" Pin 7b=0.100" Pin 8b=0.080" Pin
7c=0.180" Pin 8c=0.200" Pin 7d=0.080" Pin 8d=0.080"
---------------------------------------------------------------------------
FIGURE 12
Pin 9a=0.060" Pin 10a=0.060" Pin 9b=0.160" Pin 10b=0.140" Pin
9c=0.120" Pin 10c=0.140" Pin 9d=0.100" Pin 10d=0.100"
Pin 11a=0.060" Pin 12a=0.060" Pin 11b=0.120" Pin 12b=0.100" Pin
11c=0.160" Pin 12c=0.180" Pin 11d=0.100" Pin 12d=0.100"
---------------------------------------------------------------------------
FIGURE 13
Pin 13a=0.040" Pin 14a=0.040" Pin 13b=0.180" Pin 14b=0.160" Pin
13c=0.100" Pin 14c=0.120" Pin 13d=0.100" Pin 14d=0.100"
Pin 15a=0.040" Pin 16a=0.040" Pin 15b=0.140" Pin 16b=0.120" Pin
15c=0.140" Pin 16c=0.160" Pin 15d=0.100" Pin 16d=0.100"
__________________________________________________________________________
When the engineer's key 31 is inserted into the keyway of the lock,
the "a" pins are displaced a distance equal to the corresponding
cuts in the shank of the key. The "b" pins unlock the plug 25 from
the inner cylinder and the "d" pins unlock the middle cylinder from
the outer cylinder 22. The "c" pins lock inner and middle cylinders
together. Pawl 41, carried on the plug 25, is made to rotate in a
clockwise direction, turning the inner cylinder through one quarter
revolution. The inner cylinder 24 to which the ratchet pawl head 40
is affixed and middle cylinder is thus made to rotate through one
quarter revolution. Plug and pawl are now returned to their
original positions and the key is removed from the lock, leaving
the inner and middle cylinders in their advanced positions.
The new set of "b" pins and "c" pins, having the same overall
length, but of different individual lengths, have now changed the
combination so that a new guest key will have to be employed before
the lock can be opened. The "a" pins and "d" pins retain their
original length.
The rotational relationship of the inner and middle cylinders and
the plug are clarified in FIGS. 14 and 15 which show the change of
combination by using a circular slide rule pin tumbler chart 60
having independently rotatable discs 61, 62, 63, 64 and 65. Each
disc may be rotated to simulate the quarter turn of the respective
cylinders and plug. The number of changes is very high and may be
computed for any specific application with the formula
P.sub.r.sup.n =n.sup.r where n is the total number of pins
contained in a radial pin assembly and r is the number of
assemblies in use. Thus, let us say that each assembly contains two
raceways with one pin in each raceway and that five assemblies are
in use. Then P.sub.5.sup.2 =2.sup.5 =32 combination changes
available.
This particular design is ideal for use in apartment buildings. If
the average tenant remains 6 months in one suite of rooms, it will
take 16 years to use up the available combination changes, after
which all combinations, in their proper order, will automatically
repeat themselves. In this particular design, there will be nr=10
pins in each combination change. Therefore, the lock will use a
conventional two-bitted, flat key.
A door lock that is ideal for use in offices, storefronts and home
rentals would have, for example, P.sub.3.sup.2 =2.sup.3 =8
combination changes, or P.sub.4.sup.2 = 2.sup.4 =16 combination
changes. Two housing pins 51 and 52 shown in FIG. 3 will convert
these from 6 to 8 pins respectively. The purpose of the housing
pins is to prevent the key from being withdrawn until the plug and
inner cylinder has been returned to the upright position. Hotels
and motels will probably require the use of locks having one
thousand or more combination changes (P.sub.5.sup.4, for
example).
These locks, by reason of the number of pins employed, are
virtually pick-proof. Top security applications, nevertheless, may
require the use of locks having as many as one-hundred-thousand
combination changes (P.sub.5.sup.10), or even one million
combination changes (P.sub.6.sup.10). The physical dimensions of
these locks, in most cases, will be no greater than those in
today's market.
Any lock in which n is greater than 2 will require the use of a
barrel type key, but these acquire a feature of dependability
unexcelled by existing locks. The number of bits in any case is
equal to n.
A master combination can be designed into the guest lock simply by
cutting the center pins, but then, if a master key is lost, stolen,
duplicated or sold (selling of these keys is common) it would be
necessary to disassemble every lock in the hotel, motel or other
establishment in order to change the master combination. It is
easier, wiser and more economical to use a service lock in which
the master combination can be changed as easily and as quickly as
the guest combination. As a matter of fact, this procedure is
absolutely necessary for the safety and complete protection of the
tenants. The service lock will be designed into the system in such
a way as to bypass the guest lock.
A very good service lock, using a conventional two-bitted key is
found to have P.sub.5.sup.2 =2.sup.5 =32 10-pin combinations. These
are converted by the housing pins to combinations having 12 pins
each. This particular lock, also, is ideal for use in apartment
building and/or office buildings in which the combination will be
changed only two or three times a year.
While particular embodiments of the present invention have been
shown and described, it will be obvious to those skilled in the art
that changes and modifications may be made without departing from
this invention in its broader aspects, and, therefore, the aim in
the appended claims is to cover all such changes and modifications
as fall within the true spirit and scope of this invention.
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