Information
-
Patent Grant
-
6295725
-
Patent Number
6,295,725
-
Date Filed
Wednesday, February 9, 200024 years ago
-
Date Issued
Tuesday, October 2, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
- Hughes; S. Thomas
- Hong; John C.
-
CPC
-
US Classifications
Field of Search
US
- 029 804
- 029 432
- 029 275
- 029 281
- 029 283
- 029 34 R
- 428 544
- 428 577
- 083 518
- 070 372
- 070 373
- 070 431
- 070 466
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International Classifications
-
Abstract
A method and apparatus for the installation of interchangeable core lock caps that replace the prior art individual cap installation techniques with one that, with in a single highly repeatable operation, punches the caps for a plurality of pin chambers from a strip of appropriate metal and frictionally fits them into the plurality of pin chambers. The method and apparatus of the present invention reduce the possibility of misalignment of the caps with the pin chambers to virtually zero and eliminate entirely the need to handle the small caps. These advantages are achieved by: 1) placing a lock core having pin chambers in a fixture below a slanted die having apertures registered with the pin chambers; 2) placing a strip of metal in a fixed position over the die; and 3) through a mechanical plunger linked to a plurality of punches, driving the plurality of punches sequentially through the metal strip to form punched metal caps. The punched metal caps are then driven into frictional engagement with the registered pin chambers of the lock core through continued action of the plunger and punches.
Description
FIELD OF THE INVENTION
The present invention relates to apparatus used by locksmiths for the assembly of interchangeable core locks and more particularly, to an improved such device and process that simplifies and shortens the duration of such an operation.
BACKGROUND OF THE INVENTION
In cylinder locks of conventional design, a cylindrical key-receiving plug having a first series of radially disposed channels is rotatably mounted within a cylindrical bore in a housing having a second matching series of channels known as “pin chambers”. The pin chambers are in coaxial alignment with the first series of channels and open upon the bore. The opposite extremities of the pin chambers, furthest from the bore, are closed. Each pin chamber is adapted to confine a coil spring in abutment with the closed extremity, and a bottom pin that is urged toward the key-receiving plug by the spring. In some cases, one or more top pins, control pins or master pins may be positioned between the spring and the bottom pin within the pin chamber. The combination of pin lengths determines a code for opening the lock.
In certain types of cylinder locks, generally referred to as interchangeable core locks, the portion of the housing that contains the plug and pin chambers is part of an assembly known as a “core” that is slideably removable from the lock when released by a control key. The controlled removeability of the core is desired by institutions and others where a high turnover of employees necessitates a periodic change of locks to maintain security. Cores of several different codes may be kept by the institution, all keyed to a single control key but requiring different operating keys to open the individual locks. Changing of the locks requires a total recoding of the core to accept another key. In such a case, assembly of a new and different core is required.
The core further contains the cylindrical bore that houses the key receiving plug and the wall of the bore has a series of apertures axially aligned with the first series of channels and diametrically opposed thereto. The extremities of the pin chambers furthest from the bore are closed by means of friction fit discs or “caps” as they are commonly called. Assembly of the core requires insertion, in the proper order of bottom pins, master pins, control pins, top pins, springs and finally caps into the pin chambers. As all of these parts are very small, assembly can be a long and tedious operation. Insertion or application of the caps can be a particularly frustrating part of the operation. The caps are very small and, in addition to the obvious problem of inserting them into the similarly small pin chambers, they must be squarely and precisely aligned in order to achieve the appropriate friction fit. They must then somehow be driven into the pin chamber by striking with a hammer, mallet or the like to achieve the friction fit. Misalignment entails removal of the cap and reinsertion with the possibility of further misalignments before proper cap installation is achieved. This operation must be repeated for each pin chamber of which there are conventionally either six or seven.
Thus, a method and apparatus that would permit simplified, convenient and aligned installation of a plurality of friction fit caps into the pin chambers of a core all at one time would be highly valued by locksmiths.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to provide a simplified, convenient and accurate method for achieving multiple cap insertion that obviates the need for cap handling and assures proper alignment and insertion of all of the caps into all of the pin chambers of a single core on the first attempt.
It is another object of the present invention to provide an apparatus that makes the operation of installing the multiple caps into the pin chambers simple, convenient and accurate.
SUMMARY OF THE INVENTION
According to the present invention, there are provided a method and an apparatus for the installation of interchangeable core lock caps that replace the prior art individual cap installation techniques with one that, with a single mechanical stroke, punches the caps for a plurality of pin chambers from a strip of appropriate metal and frictionally fits them into the plurality of pin chambers. The method and apparatus of the present invention reduce the possibility of misalignment of the caps with the pin chambers to virtual zero and eliminate entirely the need to handle the small caps.
These advantages are achieved by: 1) placing a lock core having pin chambers loaded with the appropriate pins into a fixture, inserting springs into the core, the fixture has a slanted die with apertures registered with the pin chambers; 2) placing a strip of metal in a fixed position over the die; and 3) through a mechanical plunger linked to a plurality of punches, driving the plurality of punches sequentially through the metal strip to form punched metal caps. The punched metal caps are then driven into frictional engagement with the registered pin chambers of the lock core through continued action of the plunger.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a blown apart view of an interchangeable core assembly of the type for which the method and apparatus of the present invention are designed to assemble.
FIG. 2
is a front cut away view of the core assembly apparatus of the present invention.
FIG. 3
is a side cut away view of the core assembly apparatus of the present invention.
FIG. 4
is a plan view of one embodiment of the metal strip of the present invention.
FIG. 5
is a plan view of another embodiment of the metal strip of the present invention.
FIG. 6
is a plan view of yet a further alternative embodiment of the metal strip of the present invention.
FIG. 7
is a plan view of yet a fourth alternative embodiment of the metal strip of the present invention.
DESCRIPTION OF THE INVENTION
As shown in
FIG. 1
, interchangeable core lock
10
of the type assembled in the apparatus and according to the method of the present invention comprises a shell
12
, a sleeve
14
that inserts into shell
12
, a key stop and plug retainer
16
at the end of shell
12
, a plug
18
that inserts into sleeve
14
and receives key
20
. Pin chambers
22
begin in shell
12
, pass through sleeve
14
and finally enter plug
18
where they permit engagement of key
20
with the various pins inserted therethrough.
Inserted through pin chambers
22
are a variety of pins, each designed to provide a code for the various control, master or individual keys described above. As shown in
FIG. 1
, these comprise: bottom pins
24
, master pins
26
, control pins
28
and top pins
30
. Inserted into pin chambers
22
on top of these pins are springs
32
that force the pin stack against the inserted key and finally caps
34
that are frictionally fit into pin chambers
22
and retain springs
32
and the various pins in chambers
22
. It is caps
34
whose insertion and frictional fitting has been discussed herein above and whose installation is the objective of the present invention.
Referring now to
FIGS. 2 and 3
, the apparatus
36
of the present invention comprises a plunger mechanism
38
mechanically linked via, for example roll
40
, to a plurality of punches
42
that lie in registration with the apertures
44
in die plate
46
. Apertures
44
in turn, lie in registration with pin chambers
22
in plug
18
and shell
12
of lock core
48
that is secured in interchangeable lock core gripping device
49
. Gripping device
49
comprises an aperture or chamber of a size and shape to receive an interchangeable lock core
48
and, when interchangeable core
48
is fully inserted into gripping device
49
, hold pin chambers
22
in registration with die plate apertures
44
. Upper surface
50
of die plate
46
is slanted for reasons that will be explained below.
As shown in
FIGS. 2 and 3
, a slot
52
is provided between bottom
54
of punch guide
55
and upper surface
50
for the insertion of a strip of appropriate metal
56
to be inserted therebetween.
In the embodiment depicted in
FIGS. 2 and 3
, depression of punches
42
is obtained by the application of pressure to cam lever
58
that rotates about axle
60
as pressure is applied. Upon such rotation, eccentric portion
62
of cam lever
58
pushes against roll
40
mounted in frame
66
on needle bearings
68
causing downward movement of punches
42
as cam lever
58
rotates against roll
40
on the surface thereof which contacts that opposite eccentric portion
62
. This downward movement of punches
42
causes their punch tips
43
to first contact and then penetrate metal strip
56
. Because of the slanted arrangement of die plate surface
50
penetration of metal strip
56
occurs in a sequential fashion with preferably no more than three of tips
43
penetrating metal strip
56
at any point in time, thereby reducing the amount of pressure that must be applied via cam lever
58
to achieve penetration of metal strip
56
by all of tips
43
of punches
42
. The angle of surface
50
is preferably between about 2° and 10° and preferably the angle is about 4°. As punches
42
continue their downward travel through reversal of the direction of cam lever
58
and the action of eccentric portion
63
, the portions of metal strip
56
punched out by tips
43
in the first rotation of cam lever
58
are forced through die plate apertures
44
and into pin chambers
22
. Because of the size and shape of punch tips
43
these portions of metal are frictionally fit into pin chambers
22
at the downward limit of travel of punches
42
.
As will be apparent to the skilled artisan, any number of mechanical linkages or arrangements can be used to force punches
42
through strip
56
and into die plate apertures
44
and pin chambers
22
, and the present invention should not be considered limited in any way to the mechanical expedient of a cam lever
58
as depicted in
FIGS. 2 and 3
. For example, an arbor press could be used as the means for applying the required pressure while punches
42
were mounted to a plate that was depressed by actuation of the arbor press. Any and all such modifications that constitute mechanical expedients to apply pressure to a set of uniform punches should be considered mechanical equivalents. Automation of this apparatus is also contemplated.
Design of punches
42
to obtain the proper size and shape of cap
34
is well within the skill of the art and will not be described in detail here. Apertures
44
in die plate
46
provide the proper sizing of caps
34
as they are punched from metal strip
56
and then frictionally inserted into pin chambers
22
. Preferably, apertures
44
are from about 0.116 to about 0.120 inches in diameter.
Strip
56
may nominally be of any suitable material; however, brass is conventionally the material of choice because of its malleability and corrosion resistance. Annealed stainless steel could also be used as strip
56
. Similarly, while the size of strip
56
is not critical to the successful practice of the present invention, the use of a strip
56
between about ⅜ and ⅝ inches wide is specifically preferred. At this width, the strip may be used twice by extracting caps
34
from one side thereof on one pass and then inverting strip
56
and extracting a second set of caps therefrom on a second pass (see for example, FIG.
4
). Generally, metal strip
56
has a thickness of between about 0.012″ and 0.030″ depending upon the hardness of the metal used for strip
56
. Conventionally, a half-bard brass is used at a thickness of from about 0.010 to 0.025″. The dimensions of slot
52
should be on the order of about 0.01″ to about 0.02″ larger than the width dimension of strip
56
. The height of slot
52
can be of any dimension that allows proper insertion of metal strip
56
and permits the required penetration of punch tips
43
into pin chambers
22
, and, according to preferred embodiments, alignment as described below.
Similarly, although metal strip
56
is depicted as being a short strip that is inserted into slot
52
at the time of use, it could also constitute a coiled strip with a payoff and a takeup on either side of slot
52
such that, as each lock core is assembled, the continuous strip
56
is advanced an appropriate interval to provide a new area for formation of caps
34
by punching of metal strip
56
by punches
42
.
According to a series of alternative preferred embodiments of metal strip
56
depicted in
FIGS. 4 through 7
, various means of locating, i.e. self aligning metal strip
56
in slot
52
can be provided. In each of the embodiments depicted in FIGS.
4
-
7
metal strip
56
is of sufficient width as described elsewhere herein to provide at least two sets of caps
34
as shown in phantom in FIG.
4
. This is accomplished by inserting metal strip
56
into slot
52
, activating apparatus
36
to form and insert caps
34
a
as previously described and then removing metal strip
56
and rotating it about its narrow axis, reinserting it into slot
52
and activating apparatus
36
to form and insert a second set of caps
34
b
. Metal strip
56
is preferably of such a length that it can then be rotated about its long axis and the just described process repeated to form and insert sets of caps
34
c
and
34
d
by further rotation and activation of apparatus
36
.
As shown in
FIG. 4
, the innermost end
61
of metal strip
56
can be provided with geometrically modified corners (in the case depicted in
FIG. 4
rectangular cutouts
57
) that bear against a locator pin(s) or the like
59
located at the rear or innermost portion of slot
52
. As will be clear to the skilled artisan, cutouts
57
can be of any geometric shape such as circular, triangular, etc. so long as locator pin
59
is of a mating configuration.
As shown in
FIG. 5
the geometric cutout
57
can be moved to the center of innermost end
61
of metal strip
56
and locator pin
59
likewise relocated to the center rear area of slot
52
.
FIG. 6
depicts yet another alternative embodiment of metal strip
56
wherein the entire face of innermost end
61
of metal strip
56
is modified to a geometric shape
65
that engages a mating configuration
67
in the rear, innermost portion of slot
52
. In this case a triangular cut is depicted, but a round cut would be similarly useful and operative.
Finally, as depicted in
FIG. 7
, metal strip
56
can be provided with an aperture
69
that engages a locator pin that forms a part of the punch assembly and descends for engagement with aperture
69
simultaneously with activation of punches
42
, but serves only to engage aperture
69
when metal strip
56
is properly registered, and inhibits downward movement of punches
42
when aperture
69
is not properly engaged.
In use, the above-described apparatus is used to insert caps as follows: 1) an interchangeable lock core
48
including the appropriate bottom pins, master pins, control pins and top pins or any combination thereof is inserted into the core gripping device
49
and oriented such that pin chambers
22
are aligned with die apertures
44
. The appropriate springs are then inserted into pin chambers
22
. According to a preferred embodiment, the design of core gripper
49
is such that upon pushing core
48
home therein, such alignment is achieved. An appropriate metal strip
56
, as described hereinabove, is inserted into slot
52
. Cam lever
58
is then first activated by rotation about axle
60
in the direction of first eccentric portion
62
driving tips
43
of punches
42
sequentially through metal strip
56
forming the caps
34
. Counter rotation of cam lever
58
on axle
60
in the direction of second eccentric portion
63
pushes caps
34
(not shown in
FIGS. 2
or
3
) through die apertures
44
and into pin chambers
22
where they are frictionally secured all at one time. Lock core
48
can then be removed from gripping device
49
and is ready for lock installation.
There has thus been described, a novel apparatus and method for obtaining the simplified and accurate installation of a plurality of caps into a lock core in a single highly repeatable operation. This significantly shortens the interchangeable lock core assembly process and provides a highly repeatable and a considerably less frustrating operation.
As the invention has been described, it will be apparent to those skilled in the art that the same may be varied in many ways without departing from the spirit and scope of the invention. Any and all such modifications are intended to be included within the scope of the appended claims.
Claims
- 1. A lock core cap installation device capable of installing a plurality of caps in a single repeatable operation comprising:A) a lock core gripping device that receives and retains an interchangeable lock core having a plurality of pin chambers; B) a die having a slanted upper surface, a lower surface and a plurality of die apertures that penetrate said die from said upper surface to said lower surface and lie in registration with said pin apertures when said interchangeable lock core is retained in said gripping device; C) a plurality of punches that lie in registration with said die apertures, are of a length to penetrate said die apertures and enter said pin chambers and of a size to form a plurality of caps of appropriate size as they penetrate a metal strip retained between said upper die surface and said punches and penetrate said die apertures and frictionally fit said caps in said pin chambers; D) a mechanism for driving said plurality of punches sequentially through said die apertures and into said pin chambers.
- 2. The lock core installation device of claim 1 further including a slot between said plurality of punches and said slanted upper surface for receipt and retention of the metal strip that is punched when said plurality of punches are driven sequentially through the metal strip and into the die apertures.
- 3. The lock core cap installation device of claim 2 wherein said upper surface is slanted at an angle of between about 2° and about 10°.
- 4. The lock core cap installation device of claim 3 wherein said angle is about 4°.
- 5. The lock core cap installation device of claim 3 wherein said die apertures have a diameter of between about 0.116 and about 0.120 inches.
- 6. The lock core cap installation device of claim 2 wherein said slot has a width ranging from about ⅜″ to about ⅝″.
- 7. The lock core cap installation device of claim 2 wherein said mechanism for driving said plurality of punches sequentially through said die apertures and into said pin chambers comprises a cam lever rotatable about an axle and having a pair of eccentric portions riding upon a roll having an arcuate surface, said roll slideably mounted in a frame, said punches engage said surface at a point thereon diametrically opposite from that engaged by said eccentric portion and rotation of said cam lever about said axle causes said roll to drive said punches through said die apertures and said metal strip forming said caps and reversal of said cam lever drives said caps into said pin chambers.
US Referenced Citations (4)