U.S. patent number 3,602,092 [Application Number 04/882,236] was granted by the patent office on 1971-08-31 for key-positioning vise assembly for automatic key cutter.
This patent grant is currently assigned to Ilco Corporation. Invention is credited to Robert H. Richens.
United States Patent |
3,602,092 |
Richens |
August 31, 1971 |
KEY-POSITIONING VISE ASSEMBLY FOR AUTOMATIC KEY CUTTER
Abstract
In a key-cutting machine of the type in which a cutter and
stylus are moved relative to a key blank and a key, an improved
vise assembly for automatically, accurately positioning the key and
blank in a predetermined tracing and cutting disposition. The vise
assembly includes a clamp head for picking up the key and blank in
a partially aligned position responsive to tripping of a switch by
insertion of a key and blank and thereafter advancing the same to a
selected tracing and cutting position automatically, thus
eliminating the likelihood that an improper cutting operation can
be performed.
Inventors: |
Richens; Robert H. (Leominster,
MA) |
Assignee: |
Ilco Corporation (Fitchburg,
MA)
|
Family
ID: |
25380179 |
Appl.
No.: |
04/882,236 |
Filed: |
December 4, 1969 |
Current U.S.
Class: |
409/83 |
Current CPC
Class: |
B23Q
35/00 (20130101); B23C 3/35 (20130101); Y10T
409/301064 (20150115); B23Q 2735/004 (20130101) |
Current International
Class: |
B23C
3/00 (20060101); B23C 3/35 (20060101); B23Q
35/00 (20060101); B23c 001/16 () |
Field of
Search: |
;90/13.05 ;83/413
;76/110 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Weidenfeld; Gil
Claims
Having thus described the invention and illustrated its use, what
is claimed as new and is desired to be secured by Letters Patent
is:
1. In an automatic key-cutting machine having a cutter, a stylus
spaced from said cutter, support means for a key and key blank and
means for relatively moving said support means and said cutter and
stylus, first and second vise means on said support means, said
vise means including an axially shiftable clamp head for supporting
a key in a first position, said head having a fixed jaw member, a
clamp jaw movably mounted relative to and shiftable toward and away
from said fixed jaw member, spring means yieldably urging said
clamp jaw away from said fixed jaw, and actuator means coupled with
said clamp jaw for shifting said clamp jaw toward said fixed jaw
against the yieldable pressure of said spring means and shifting
said clamp head in said axial direction away from said first
position upon development of clamping pressures of said movable jaw
against a key on said fixed jaw.
2. A device in accordance with claim 1 and including a lost motion
coupling between said actuator and clamp jaw.
3. A device in accordance with claim 1 and including first switch
means positioned to be tripped by said key at said first position
for energizing said actuator means, and stop means positioned to
engage against a shoulder of said key and arrest axial movement of
said key and clamp head when said key is shifted by said clamp head
to a second position axially inwardly displaced from said first
position.
4. A device in accordance with claim 3 and including second switch
means positioned to engage the base of said key in said first
inserted position, said second switch means and first switch means
being connected in series with said actuator means whereby said
actuator means can be energized only when said switches are
simultaneously closed.
5. In an automatic key-cutting machine having a cutter, a stylus
spaced from said cutter, support means for a key and key blank and
means for relatively moving said support means and said cutter and
stylus, first and second vise means on said support means spaced
apart in accordance with the spacing of said cutter and stylus,
said vise means including locking jaw means for holding said key
and blank during tracing and cutting, a key positioning mechanism
mounted on and shiftable axially relative to said locking jaw means
for aligning said key and blank relative to said vise means, and
actuator means for moving said positioning mechanism in said axial
direction relative to said locking jaw means.
6. Apparatus in accordance with claim 5 wherein said positioning
mechanism includes a fixed jaw, and a clamping jaw movable toward
and away from said fixed jaw, and said actuator means is
operatively associated with said clamping jaw, said positioning
means being shifted in said axial direction responsive to
predetermined pressure exerted by said clamping jaw against a key
disposed between said fixed and clamping jaws.
7. A device in accordance with claim 6 and including spring means
yieldably urging said clamping jaw away from said fixed jaw and
said actuator means away from said axial direction, said spring
means being effective to prevent axial shifting movement of said
positioning means under the influence of said actuator means until
predetermined pressures are exerted by said clamp jaw against said
key.
8. A device in accordance with claim 7 wherein said spring means
include first and second spring components, respectively urging
said positioning means away from said axial direction and urging
said clamp jaw away from said fixed jaw, the forces required to
overcome said second spring component being less than the forces
required to overcome said first spring component.
9. In an automatic key-cutting machine having a cutter, a stylus
spaced from said cutter, support means for a key and key blank and
means for relatively moving said support means and said cutter and
stylus, first and second vise means for positioning and clamping
said key and blank during cutting and tracing, said vise means
including a clamp head having a fixed jaw, a bellcrank lever
pivotally mounted on said clamp head and including a clamp jaw arm
and a actuator arm, first spring means yieldably urging said lever
to a key-receiving pivoted position in which said clamp jaw arm is
spaced from said fixed jaw, actuator means operatively connected to
said actuator arm for urging said arm in said axial direction,
thereby to pivot said clamp jaw arm toward said fixed jaw and
thereafter to shift said clamp head in said axial direction upon
development of clamping pressures of said jaw arm against a key
disposed between said fixed jaw and jaw arm.
10. A device in accordance with claim 9 and including second spring
means yieldingly urging said head away from said axial direction,
the forces required to shift said head in said axial direction
against said second spring means exceeding the forces required to
pivot said clamp arm against the influence of said first spring
means.
11. A key-cutting apparatus including cutter and tracer means,
support means movable relative to said cutter and tracer means and
vises for holding a key and key blank on said support means, each
said vise including a locking jaw, clamp head means movably mounted
relative to said locking jaw for gripping a key and shifting said
key axially relative to said locking jaw, switch means operated
responsive to insertion of a key into said clamp head to a first
position for fixing said key to said clamp head against relative
movement and actuator means operated responsive to the fixing of
said key to said clamp head for shifting said clamp head to a
predetermined indexed position relative to said locking jaw, thus
to advance said key to a second, predetermined position.
12. A device in accordance with claim 11 and including means for
clampingly engaging said locking jaw against said key responsive to
relative movement of said support means and cutter and tracer
means.
13. A device in accordance with claim 11 and including holddown
means positioned to engage said key and blank for seating the bases
of said key and blank in said vises, means for clearing said
holddown means from engagement with said key and blank during the
tracing and cutting of said blank and said key, said switch means
being mounted on said holddown means.
14. The combination of claim 11 and including stop means on said
support means positioned in the path of movement of a key held in
said clamp head to engage and locate said key in said indexed
position.
15. The combination of claim 14 and including a lost motion
coupling connected between said actuator means and said clamp
head.
16. The combination of claim 15 wherein said lost motion connection
includes a tension spring whereby said key is yieldingly held
against said stop means.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is in the field of key-cutting machines, and more
particularly key-cutting machines of the type in which a cutting
wheel and a tracing stylus are movably mounted relative to a pair
of spaced vises for holding a key blank and a key.
More particularly, this invention is in the field of cutting
devices of the type described in which the various operations are,
to a maximum extent, automatically performed.
2. The Prior Art
It is conventional to cut keys by providing a cutter wheel stylus
on the one hand, and a pair of vises on the other hand. The vises
may be charged with a key and key blank which are located in
precise positions within the vises by pressing a portion of the key
(normally the shoulder) against a reference or indexing portion of
the vise.
A relative movement is then effected between the vises on the one
hand and the cutter and tracer on the other, the movement being
dictated by utilizing the engagement of the tracer against the
pattern of the key to induce a concomitant movement between the
cutter and the key blank, thus, in effect, milling the blank to
conform to the pattern of the key.
In accordance with more recent adaptations of the above-described
cutting machine concept, various phases of the key-cutting
operation have been automatically carried out. For instance, it is
known to provide mechanism for automatically relatively moving the
vises in relation to the tracer and cutter.
In other machines the operation of developing clamping pressures
for the key and key blank within the respective vises has been
automatically carried out as a function of the operation of the
device.
In still further developments, the insertion of the key and the key
blank has been relied on to initiate the key-cutting cycle,
including the clamping of the key and blank, the movement of the
key and blank relative to the tracer and cutter, and the release of
the key and blank at the completion of the cutting operation, to
permit removal of the same from their respective vises.
It has been the consistent intention of designers of the various
forms of key-cutting machines to arrive at an apparatus which is
essentially foolproof, to the end that even persons totally
inexperienced in the field of locksmithing and key cutting can, by
following certain simple directions, produce a perfect replica or
duplicate key.
Although a multiplicity of machines have been proposed to meet this
end, no known cutter has heretofore been available by which
completely satisfactory results can be consistently achieved. A
principal difficulty in all cases has been the tendency or
possibility that an inexperienced user might insert the key or key
blank within its respective vise in such manner that the alignment
between the blank and its vise differs from the alignment between
the key and its vise. Obviously, when a cut is effected under such
circumstances, the cuts in the key blank simply will not match the
cuts in the pattern key. A mismatch of even a few thousandths of an
inch in either depthwise or axial formation of the cuts will render
the duplicate key unsuitable for operating the lock for which it
was intended.
In an attempt to facilitate accurate positioning of keys, it has
been proposed to use limit switches as locating expedients which
trigger closing of the vise in response to insertion of a key. The
theory behind such devices is that in the absence of tripping the
switch, the vises cannot be actuated. Since the switch can
presumably be tripped only with properly aligned keys, it was
supposed that such systems would provide a foolproof key-cutting
machine suitable for use, for instance, as a component of a
coin-operated key-vending apparatus. Such devices have not proved
to be practical since a significant percentage of miscut keys is
still produced.
Without limitation, failure of these devices is attributed to the
possibility of movement of the key after a switch has been
triggered, due to the inherent variations in limit switches which
permit a certain amount of overtravel after the switch is closed.
There is also the possibility, in certain such machines, that the
key may be skewed to a degree which will cause improper duplication
yet nonetheless permit triggering of the switch.
SUMMARY OF THE INVENTION
The present invention relates to an automatic key cutter including
a vise assembly, which vise assembly automatically shifts the key
and key blank inserted into their respective vises from an initial,
partly aligned position. The vise assemblies assure that the key
and key blank will be oriented with extreme accuracy relative to
their respective vises.
The vise assemblies include a movable clamp head which initially
automatically grips the key and key blank at a partially aligned
position responsive to insertion of a key and blank, and advances
the same to a second, precisely aligned position. Preferably, the
device includes secondary clamp means of more or less conventional
nature, which firmly grip the key and blank in the second position
and prevent shifting of the same in the course of cutting or
tracing.
It is accordingly an object of the invention to provide in a
key-cutting machine of the type described, automatic vise
assemblies for the key and key blank which are effective to assure
controlled positioning of said key and blank members.
It is a further object of the invention to provide an assembly of
the type described which is foolproof and, hence, suitable for use
as a component of a coin-operated vending machine or system whereby
unskilled and unsupervised persons may effect the automatic
duplication of a key.
It is a further object of the invention to provide a key-cutting
machine of the type described which incorporates a key blank vise
assembly and a key vise assembly which grasp a partially inserted
key blank and key and advance the same from an initial to a second
position relative to the vises.
To attain these objects and such further objects as may appear
herein or be hereinafter pointed out, reference is made to the
accompanying drawings, forming a part hereof, in which:
FIG. 1 is a plan view of a key-cutting apparatus in accordance with
the invention, with certain conventional components of the
key-cutting machine proper eliminated, and/or shown in dot and dash
lines, more clearly illustrating the innovative portions of the
apparatus;
FIG. 2 is a front elevational view of the apparatus of FIG. 1;
FIG. 3 is an enlarged perspective view of a vise assembly forming
the principal subject matter of the present invention;
FIG. 4 is a magnified section taken on line 4--4 of FIG. 3;
FIG. 5 is a vertical section taken on line 5--5 of FIG. 3;
FIG. 6 is an exploded perspective view of the basic components of
the vise assembly.
Turning now to the drawings, there is shown in FIG. 1 an
essentially conventional key-cutting machine which has been adapted
for automatic operation by incorporating therein a pair of key
blank and key receiving and positioning vises 10, 10' , which
constitute the principal advance hereof.
It should be understood from the outset that the vises may be
employed in any of a series of different key-cutting machines, the
specific cutting machine 11 illustrated herein being incorporated
by way of example only and for purposes of complying with the
requirements of the patent laws.
As more fully explained hereafter, the cutting machine is of the
type in which the key and key blank vises are supported on a
movable carriage, which carriage is shifted axially and pivotally
relative to a fixedly positioned key-cutting wheel and stylus. It
will, however, be appreciated that the vises are equally adapted
for use in assemblies of the type in which the vises are stationary
and the cutter and tracer are movable.
In accordance with the invention, 12 is a base or frame portion on
which is pivotally mounted a carriage assembly 13. The carriage
assembly is free to move axially inwardly and outwardly (up and
down as viewed in FIG. 1) about the carriage support rod 14. The
carriage may likewise be pivoted relative to the rod.
The frame 12 carries a motor (not shown) which may be fixed to a
depending pivotal motor mount 15, the output drive pulley (not
shown) of the motor being in driving connection with the input
pulley 16, made fast to an input shaft 17 rotatably mounted in
spaced bearings forming a part of the frame.
A conventional key cutter wheel 18 is carried on the shaft 17. A
worm 19 meshes with drive gear 20, which gear, through a
conventional secondary speed reduction gearing (not shown), slowly
rotates the shaft 21, which is likewise journaled for rotation on
the frame. The shaft 21 carries a box cam 22, having a continuous,
outwardly open cam track 23 including axial components, it being
understood that the cam track serves to drive the carriage
forwardly and rearwardly for purposes of performing the cutting
cycle and other operations hereinafter to be described.
24 is a heavy coil spring sleeved about the carriage support rod
14, the spring 24 serving to urge the carriage toward a forward
position shown in FIG. 1. A follower pin 25, made fast to the
carriage, extends into the track 23 of the box cam.
From the foregoing essentially conventional drive mechanism, it
will be appreciated that rotation of the box cam will cause the
carriage to be shifted rearwardly, compressing the spring 24, the
carriage being thereafter shifted forwardly in accordance with the
rotated position of the cam track 23.
Permanently mounted to the frame 12 is an adjustable stylus
assembly 26 incorporating a laterally extending stylus or tracer
member 27. The stylus assembly 26, as is conventional, incorporates
adjustment means for axial and lateral adjustment, the net effect
of which is to permit the tip 27' of the stylus 27 to be fixedly
and accurately positioned in predetermined spaced relation to the
cutting peripheral portion of the cutter wheel 18. The position of
the stylus must be adjusted from time to time to compensate for
wear of the cutter wheel.
It will be understood that the spacing of the stylus tip 27' and
the cutting peripheral portion of the wheel 18 is arranged to
correspond precisely with the spacing of a key and a key blank
supported within the vises 10' and 10, respectively.
In the usual manner, when the carriage 13 is shifted forwardly and
rearwardly by the box cam 22, the engagement of the stylus tip 27'
against the pattern portion of a key supported in vise 10' will
cause a sinuous pivotal or tilting movement of the carriage as the
tracer scans the key, inducing a concomitant movement of the vise
10, which is equally spaced from the pivot radius of the rod 14.
The eccentric weight orientation of the carriage would normally
tend to induce a clockwise pivotal rotation of the carriage about
the rod 14. A heavy spring member 28 links the carriage to the
frame and overcomes this clockwise moment of the carriage, inducing
a yieldable anticlockwise force, which force maintains the bits or
pattern surface of the key in contact with the tip 27' of the
stylus. In this essentially conventional manner, stylus-key contact
causes a concomitant movement of the key blank against the cutter
wheel, resulting in the milling or cutting away of the key blank to
correspond with the bitting of the pattern key.
During the actual tracing and cutting, the key and the key blank
must be immovably clamped within the vise assemblies 10' and 10.
Clamping pressures are developed by vise actuator levers 29, 29',
which actuates vises 10, 10', respectively. The vise actuator
levers are pivoted at 30, 30', respectively, to portions of the
carriage, the levers being urged in an anticlockwise direction
about such pivots by springs 31, 31', respectively.
The levers include hardened vise actuator cams 32, 32' which bear
against the upper surfaces 33, 33' of movable vise jaws 34, 34'. It
will be appreciated that the springs 31, 31' thus normally tend to
press the jaws 34 34' downwardly toward the clamping position of a
key and key blank.
The levers 29, 29' are additionally provided with lift follower
noses 35, 35', which follower noses bear against lift cams 36, 36'
fixed to the frame. The lift cams include downwardly directed
trailing follower release portions, the follower noses 35, 35'
being engaged with the highest point of the cams 36, 36' when the
machine is in its forwardmost position, as shown in FIG. 2. Due to
the slope of the lift cams 36, 36', initial rearward movements of
the carriage are accompanied by an anticlockwise movement of the
levers 29, 29' under the influence of springs 31, 31', thereby
allowing the force of the springs to press downwardly against the
moving jaws 34, 34'.
It will thus be observed that when the carriage is in its
forwardmost position, the jaws 34, 34' of the vises 10, 10' are
free to move upwardly to their open position under the influence of
lift springs 37--see FIG. 3, whereas upon initial rearward movement
of the carriage, the portions 32, 32' will be permitted to bear
against the jaws 34, 34', shifting the jaws from the open to the
closed position.
It will be further understood that upon completion of a cutting
cycle and return forward movement, the follower noses 35, 35' will
again be lifted to their highest position, relieving the pressure
on the upper surfaces 33, 33' of the vise jaws 34, 34', whereupon
the jaws are opened under the influence of springs 37.
As thus far described, the cutting machine is entirely
conventional, its operation being explained solely to permit a
clearer understanding of the novel vise assembly most clearly shown
in FIGS. 3 to 6. Since the vise assemblies 10, 10' are essentially
identical, a description of the structure and operation of vise 10
will suffice.
The vise assembly 10 includes a fixed locking jaw 40 which is made
fast to the carriage. The locking jaw includes an upstanding guide
portion 41 having parallel outer walls 42, 43 which slide against
the finer walls 44, 45 within the movable jaw 34 to permit the
movable jaw an upward and downward movement relative to the fixed
jaw 40. The fixed jaw is provided with a opposed pair of axially
extending, outwardly open guide slots 46, 47.
A clamp head assembly 48 incorporates a pair of axially extending
spaced legs 49, 50, the inner opposed portions of which legs are
slidably received in and guided for axial movement on the slots 46,
47, respectively. An end bar 51 is mounted on the inner terminal
ends of the legs 49, 50, the engagement of the bar 51 against the
rear portion 52 of the fixed vise jaw 40 providing an outward limit
stop for the clamp head assembly 48.
The clamp head assembly is provided with a recessed key receiver
slot 53. A clearanceway 54 is formed downwardly through the upper
face 55 of the end portion 56 of the clamp head assembly to provide
clearance for actuation of the key-clamping components hereinafter
to be described.
In the clamp head assembly, the under surface 57 forms a fixed
clamp jaw, against which the under surface of the key will be
disposed. The movable or upper clamp jaw 58 comprises an eccentric
cam having a depending lobe 59. The cam is mounted on a pivot pin
60, the opposed ends of which pin are journaled in spaced coaxial
bores 61, 62 formed in the clamp head 56 in alignment with the key
receiver slot 52.
A bellcrank arm 63 is fixed to the pin and cam 58, the upper end 64
of the arm being provided with a pivot pin 65, which pin is
pivotally connected to the inner end 66 of an actuator arm 67. It
will be observed, with particular reference to FIG. 4, that a
left-to-right movement of the actuator arm 67 will cause a
clockwise movement of the pin 60 carrying the depending lobe 59 of
clamp jaw 58 downwardly against the upper surface of the key, thus
to wedge or bind the key tightly against the upper surface 57 of
the clamp head assembly. Clearance for the movement of the
bellcrank lever 63 is provided through the upwardly extending
recess or clearanceway 54 in the clamp head assembly 48.
The clamp head 48 thus provides a initial clamping action against
the head portion of the key. The final clamping action, i.e. the
permanent clamping during the tracing and cutting of the key, is
effected by the downward pressure of the vise jaw 34 against the
lifting action of springs 37.
When the jaw 34 is depressed in the manner previously described,
the horizontal under surface 68 of the jaw is brought to bear
against an upper side part of the blade portion 69 of the key K.
When the key is positioned within the slot 53, a portion of the
under surface of the blade 69 is disposed atop the leg 49 of the
clamp assembly, which leg is in coplanar alignment with surface 57
of the clamp head assembly.
As best seen in FIG. 6, the left-hand-most portion of the blade,
i.e. the portion which will be cut or traced, projects laterally to
the left beyond the vise assembly 10, to permit access thereto of
the cutter wheel or stylus without interference with the vise.
Thus, when the movable vise jaw 34 is depressed, the key blade will
be tightly clamped between the under surface 68 of the jaw 34 and
the upper surface 49' of the leg 49 of the clamp head assembly.
The upper jaw 34 has an axially directed clearance slot 70 to
provide room for axial movement of the actuator arm 67. The rear
end 71 of the actuator arm is guided for axial sliding movement
relative to the drawbar 72, which drawbar is fixed to a solenoid
assembly 73. Optionally, to provide the desired guiding function
while permitting axial relative movement, the end 71 of the
actuator arm 67 may have ears 74 embracing the drawbar.
Solenoid 73 includes a plunger 75, connected at 76 to the drawbar
72. A tension spring 77 is connected between aperture 78 on the
actuator arm 67 and aperture 79 forming a part of the drawbar
assembly. It will thus be observed that a rearward movement of the
plunger 75 of the solenoid will carry the drawbar axially
rearwardly with it, an the rearward movement will be likewise
imparted to the actuator arm 67 through the medium of the tension
spring 77. The coupling between the drawbar and the actuator arm
may be properly described as a lost motion coupling since, when
further rearward movement of the drawbar is prevented, e.g. by the
lobe 59 being blocked against further movement by contact with a
key K, the drawbar and, hence, the plunger is still permitted a
further degree of rearward travel so that the plunger may proceed
to its limiting position relative to the solenoid. By permitting
the solenoid plunger to seat, chattering of the solenoid, as might
be experienced if the plunger were prohibited from proceeding to a
seated position, is prevented.
The mechanism for depthwisely positioning the key and for
preventing relative tilting of the key and vise will next be
described.
Depthwise location is effected responsive to a pair of switch and
stop assemblies 80, 80' mounted on a shutter assembly 81 which is
pivotally secured to the carriage. The switch and stop assemblies
80, 80' are identical in all respects, save that the means for
seating (i.e. applying lateral force to) the pattern key in the
vise 10' is independently pivotally mounted, whereas the force for
holding the key blank in the vise 10 is a function of the pivotal
force imparted to the entire shutter assembly. Accordingly, for
purposes of clarification, the positioning assembly 80' will be
described since much of the assembly 80 (as viewed in FIG. 3) is
concealed by illustrated components of the vise 10.
The shutter 81 is pivotally mounted to the carriage by the pivotal
connection of bearing aperture 82 on the headed trunnion 83 (see
FIG. 2) made fast to the carriage. A tension spring 84 is connected
between the shutter 81 and a portion of the carriage, to impart a
clockwise biasing influence to the shutter. A portion 85 of the
shutter 81 adjacent the vise assembly 10 presses against the key
inserted into the vise assembly 10, the force of spring 84 thus
biasing the base 86 of the key against outer wall 43 of the fixed
jaw 40, serving as a reference point.
In the positioning assembly 80', the seating function performed by
the part 85 is effected by a pivotal lever 85' mounted on pivot pin
86'. Spring means (not shown) bias the lever 85' in a clockwise
direction, to permit the lever to serve the pattern key-seating
function served in connection with vise 10 by the part 85. The use
of independent holddown parts 85, 85' is required since the
heightwise dimension of the key and key blank may vary, and the
insertion of a key blank in the vise 10 would thus relieve tension
and prevent the seating of a key in vise 10', should the height of
the key blank exceed the height of the pattern key.
The shutter assembly 81 is pivoted in a counterclockwise direction
clear of its screening relation of the vises in the course of the
cutting and tracing action previously described. The pivoting of
the shutter is caused by the interaction of a depending follower
lobe 87 on the shutter against inclined cam 88 on the stationary
frame 12 (see FIG. 2), it being understood that as the carriage
moves rearwardly, the lobe 87 rides up the cam face 88 and the
shutter is counterclockwisely pivoted against the action of the
spring 84. When the carriage moves forwardly again, the lobe is
cleared from the raised surfaces of the cam 88, permitting return
movement of the shutter 81.
The positioning assembly 80' includes an upwardly extending arm 90,
having a right angular recess 91 formed therein. A support leg 92,
of lesser height than the arm 90, parallels the lower portion of
the recess. A bellcrank switch actuator lever 93 is mounted in the
recess 91 between the arm 90 and the leg 92. A pivot pin 94 extends
through the junction between the upper leg 95 of the bellcrank
lever arm and the lower leg 96 thereof.
As best seen in connection with the composite assembled vise 10
shown in FIG. 3, the upper leg 95 of the bellcrank lever 93 will be
disposed in the path of the shoulder portion 97 of a key inserted
into the slot 53 of the clamp head assembly. An actuating
microswitch 98 is mounted to the front face of the shoulder 81 in
such manner that its depressible switch contact 99 is disposed in
alignment with the bellcrank lever 93.
The lower leg 96 of the lever includes a forwardly directed,
inclined cam face 100. Spring means (not shown) project the upper
leg 95 of the bellcrank lever forwardly, i.e. in the direction of
insertion of the key, thus causing the cam surface 100 to be
normally displaced rearwardly of the movable contact 99. It will be
observed, however, that when a key is inserted through the slot so
that its shoulder is pressed against the upper leg portion 95, said
upper portion will be pivoted inwardly, inducing a forward movement
of the leg 96, causing the cam 100 to depress the contact 99,
closing the circuit through the microswitch 98.
In order to assure that the base 86 of the key is in precise axial
alignment with a vise, each vise is equipped with a side alignment
microswitch 101. The microswitch 101 is mounted on the fixed vise
jaw 40 and includes a laterally directed, spring-projected contact
plunger 102 which extends through a cross bore 103 in a fixed jaw
into the path of the base 86 of the key. As best seen in FIG. 3,
the base of a properly aligned key will depress the plunger 102,
closing the circuit through microswitch 101.
Optionally but preferably, depthwise and sidewise alignment
microswitches of each vise are connected in series so that the
solenoids 73 controlling the respective vises cannot be actuated
unless both switches are simultaneously depressed.
It is important to recognize that the microswitch 98 does not
perform a depthwise alignment function. Rather, this switch, unlike
prior art key-activated switching apparatuses, performs an
energizing function, with final, accurate depthwise positioning
being accomplished by automatic means in a manner hereinafter
described.
A key is inserted in the vise through the slot 53 in such manner
that its base 86 depresses the plunger 102, to close microswitch
101. Continued inward movement of the key will cause the key
shoulder 97 to engage against upper leg portion 95 and a bellcrank
lever 93 to induce a forward pivoting of the lower leg 96 of the
bellcrank lever, causing the cam surface 100 to depress the trip
contact 99 of microswitch 98. Assuming that microswitches 98 and
101 of each vise to be wired in series with a solenoid assembly 73
and a source of current, it will be observed that the solenoid will
then be energized, causing inward movement of the plunger 75, which
plunger is normally maintained in a forward position by spring 104
tensioned between the plunger and a fixed portion of the frame.
Rearward movement of the plunger induces a rearward shifting
movement of the drawbar 75 and, through the linking action of
spring 77, the actuator arm 67. Rearward movement of the actuator
arm causes a rotation of the pin 60 carrying clamping lobe 59,
causing the clamping lobe 59 to press against the upper surface of
the key.
The entire clamp head assembly 48 is free to slide forwardly and
rearwardly relative to the fixed jaw 40 by reason of the previously
described sliding engagement of the legs 49, 50 within the slots
46, 47. Spring means 105, compressed between a fixed portion of the
frame and the bar 51, normally projects the clamp head to a forward
position. This spring means is effective to maintain the clamp head
in the noted forward position during the initial rearward movements
of the actuator arm 67, i.e. until clamping pressures are developed
between the lobe 59 connected to the actuator arm and the upper
surface of the key. One such clamping pressures are developed, the
contained rearward movement of the actuator arm 67 bodily carries
with it the entire clamp head assembly 48. Inward axial movement of
the clamp head assembly 48 results in a continued pivotal movement
of the bellcrank lever 93 by reason of the engagement of the key
shoulder against the leg 95 of the lever. In the course of this
continued movement, the cam surface 100 may further depress the
switch contact 99 beyond the amount required for initial energizing
of microswitch 98. Thus, the clamp head assembly will continue to
move rearwardly until the rear face of the upper leg 95 of the
bellcrank lever bottoms against the forwardly directed face 106 of
the channel or cutout 91 in arm 90. When the lever leg 95 is thus
bottomed, further axial inward movement of the clamp head 48 will
be positively prevented However, as previously noted, the solenoid
plunger may continue its inward movement, due to the lost motion
coupling connection between the drawbar 72 and the rear end 71 of
the actuator arm 67.
It will thus be apparent that when a key or key blank is inserted
into one of the vises 10 or 10', the key is sequentially gripped by
the clamp head without any rearward movement of the clamp head and,
after gripping is effected, the key is carried further inwardly to
a bottom reference position relative to the vise.
By connecting the side alignment switch in series with the
solenoid, it will be apparent that the clamp head assembly simply
cannot be activated unless the base 86 of the key is in the exact,
desired axial alignment.
Final depthwise referencing of the key and key blank is
accomplished after initial tripping of the clamp mechanisms, thus
to assure that the final setting movements of the key are
accomplished by a precise axial inward movement of the key. Such
precise axial inward movement is in contradistinction to
key-cutting machines heretofore known wherein operation of a start
switch is triggered by insertion of a key, the switch also being
relied on to position the key. In all such known devices, there us
a time interval between the tripping of the start switch by
insertion of the key and the actual gripping of the key by the key
machine mechanism. Without limitation, the failure of such
key-cutting machines is considered, in large measure, to result
from the possibility that the key may initially be inserted in a
proper referenced position to trip a start switch, but during the
time lag or interval between tripping of the switch and gripping of
the key, the manual pressure employed to seat the key against the
switch may induce a tilting or canting of the key.
The tendency toward unseating of the key from its aligned position
in heretofore known devices is accentuated by the fact that the
limit switch or other means utilized as the depthwise positioning
means for the key, is powered by springs, which springs normally
oppose the insertion of the key. Thus, should a user insert a key
until the switch is activated by release the key immediately upon
activation of the switch, the very act of releasing the key
prematurely will subject the key to an unseating action by the
limit switch. Accordingly, when the clamping mechanism finally
permanently fixes the position of the key, the key will have been
displaced a significant amount from its desired indexed
position.
The problem in prior known machines is magnified by the fact that
even a series connection employing such switch may not be relied on
to deactivate the circuit of the machine since it is possible to
insert a key beyond the distance necessary to trip a microswitch.
In other words, even the protection of a series connected circuit
is of no avail where the microswitch is tripped at a first position
and continues to remain closed when the key is shifted beyond such
position.
The device of the present invention overcomes the above-noted
drawbacks by avoiding reliance on the microswitch as a
depth-positioning means, and utilizing instead the switch to
trigger means for clamping and thereafter moving the key until the
shoulder is yieldably pressed firmly against a stop surface.
The final seating movement is effected by a precisely axially
directed force. The lost motion coupling between the clamp head and
the solenoid permits an overtravel in the manner previously set
forth, thus permitting the unit to accommodate keys of a wide
variety by varying dimensions.
Optionally but preferably, the circuitry which activates the
key-cutting motor may be made responsive to the proper operation of
the two vise members so that the key-cutting motor may not be
energized through a cutting cycle until after the clamp heads of
the two vises have engaged and advanced the key and key blank to
the desired position.
From the foregoing it will be appreciated that in the device of the
present invention the insertion of a key and blank results in an
automatic positioning of the same in such manner that the key and
blank are precisely disposed in a predetermined aligned position in
the vises, whereby the pattern of a cut key is accurately
reproduced on a key blank. The possibility of mispositioning either
the key or the blank is eliminated. Since the concluding movements
of seating the key and key blank against a desired reference
shoulder or stop are effected, after initial clamping, by a
precisely axially directed shifting mechanism, there is no
possibility of misalignment of the key and blank, as is the case in
other so-called automatic key-cutting machines heretofore known in
which the key and/or the blank must be manually inserted into their
ultimate positions.
It will be readily appreciated that the vises are not restricted in
their application to key-cutting machines of any specific type but,
rather, may advantageously be included in any automatic key-cutting
machine.
The key-cutting device is particularly adapted for use in
coin-operated vending machines due to the foolproof and fail safe
nature of the loading procedure. Also, due to the automatic loading
feature of the machine, the cutter may advantageously be employed
in high volume key-cutting establishments wherein a single operator
may be able simultaneously to operate several machines, due to the
rapidity with which the machines may be loaded and the fact that
the device requires no attention, once the key and blank have been
inserted.
It will be understood that variations may be made of the concepts
hereof without departing from the spirit of the invention and,
accordingly, the invention is to be broadly construed within the
scope of the appended claims.
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