U.S. patent number 3,894,415 [Application Number 05/454,420] was granted by the patent office on 1975-07-15 for combination padlock.
This patent grant is currently assigned to Presto Lock Company, Division of Walter Kidde & Company, Inc.. Invention is credited to Lazlo Bako.
United States Patent |
3,894,415 |
Bako |
July 15, 1975 |
Combination padlock
Abstract
A combination padlock of the single dial type is constructed so
that maniation of the shackle enables changing or setting the
combination, thereby eliminating additional elements to accomplish
this function. The padlock employs a floating fence member which
acts as a single or double lever on different occasions. A
key-actuatable bolt cooperable with the fence member enables the
padlock to be opened by a key.
Inventors: |
Bako; Lazlo (Woodcliff Lake,
NJ) |
Assignee: |
Presto Lock Company, Division of
Walter Kidde & Company, Inc. (Elmwood Park, NJ)
|
Family
ID: |
23804530 |
Appl.
No.: |
05/454,420 |
Filed: |
March 25, 1974 |
Current U.S.
Class: |
70/21; 70/316;
70/25; 70/321 |
Current CPC
Class: |
E05B
37/0068 (20130101); Y10T 70/7328 (20150401); Y10T
70/415 (20150401); Y10T 70/7356 (20150401); Y10T
70/424 (20150401) |
Current International
Class: |
E05B
37/00 (20060101); E05b 037/10 () |
Field of
Search: |
;70/21,25,316,317,318,321,322,401,407 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wolfe; Robert L.
Attorney, Agent or Firm: Shapiro and Shapiro
Claims
I claim:
1. A combination padlock comprising:
a body having an internal cavity;
a shackle having a long leg portion and a short leg portion, the
long leg portion extending into the internal cavity and being
slidably supported by the body for enabling the shackle to be moved
from an open first position to a closed second position and to a
combination-changing third position;
a manually rotatable dial supported by the body;
a plurality of tumblers contained in the internal cavity, the
tumblers being rotatable by the dial;
locking means cooperable with the tumblers for locking the shackle
in the closed second position and for unlocking the shackle when
the tumblers are set to the opening combination of the padlock;
and
combination-changing means actuated by the long leg portion of the
shackle when the shackle is moved to the combination-changing third
position for enabling the opening combination of the padlock to be
changed.
2. A combination padlock as set forth in claim 1, wherein the
tumblers releasably engage associated tumbler drivers, the drivers
being rotatable by the dial, and wherein the combination-changing
means comprises means for disengaging the tumblers from their
associated drivers when the shackle is in the combination-changing
third position, thereby enabling the drivers to be manually rotated
relative to their associated tumblers by the dial for setting a new
opening combination.
3. A combination padlock as set forth in claim 2, wherein the means
for disengaging the tumblers from their associated drivers
comprises shifter means for shifting the tumblers relative to their
associated drivers in a direction substantially along the axis of
rotation of the tumblers.
4. A combination padlock as set forth in claim 3, wherein the
shifter means comprises a shifter plate having one end pivotally
supported by the body and the other end biased into contact with
means provided by the long leg portion of the shackle, the shifter
plate carrying a pair of spaced side plates having slots receiving
the peripheral edges of the tumblers, movement of the shackle from
the open first position to the combination-changing third position
causing the side plates to be moved in directions substantially
parallel to said axis for moving the tumblers out of engagement
with their associated drivers.
5. A combination padlock as set forth in claim 4, wherein the means
provided by the long leg portion of the shackle has means for
scrambling the combination as the shackle is moved from the closed
position to the open position.
6. A combination padlock as set forth in claim 1, wherein the
locking means comprises a fence member having one end slidably
connected to rail means provided by the body, the fence member
having engagement means near its other end for releasably engaging
the short leg portion of the shackle to lock the shackle in the
closed position, and having projecting means intermediate the one
end and the engagement means, and a spring which acts against the
fence member between the one end and the projecting means for
biasing the one end of the fence member toward one end of the rail
means for biasing the projecting means into contact with the
peripheries of the tumblers, the engagement means engaging the
short leg portion of the shackle for locking the shackle when the
shackle is in the closed position and the projecting means being
receivable by notches in the peripheries of the tumblers for moving
the engagement means out of engagement with the short leg portion
of the shackle to unlock the shackle when the tumblers are set to
the opening combinations.
7. A combination padlock as set forth in claim 1, further
comprising a ring disposed in the internal cavity and rotatable by
a key, the ring having means for moving the engagement means of the
fence member out of engagement with the short leg portion of the
shackle when the ring is rotated in a first direction by the
key.
8. A combination padlock as set forth in claim 6, further
comprising a ring disposed in the internal cavity and rotatable by
a key, the ring having means for moving the engagement means of the
fence member out of engagement with the short leg portion of the
shackle when the ring is rotated in a first direction by the
key.
9. A combination padlock as set forth in claim 1, wherein the
combination-changing third position is reached by rotating the
shackle from its usual open position and then pushing the long leg
portion of the shackle into the internal cavity.
10. A combination padlock as set forth in claim 1, further
comprising means for preventing the combination of the padlock from
being changed when the shackle is in the combination-changing third
position unless the tumblers are set to the opening
combination.
11. A combination padlock as set forth in claim 4, wherein the
locking means comprises a fence member having one end slidably
connected to rail means provided by the body, having engagement
means near its other end for releasably engaging the short leg
portion of the shackle for releasably locking the shackle in the
closed position, and having projecting means intermediate the one
end and the engaging means, and a spring which acts against the
fence member between the one end and the projecting means for
biasing the one end of the fence member toward one end of the rail
means and for biasing the projecting into contact with the
peripheries of the tumblers, the engagement means engaging the
short leg portion of the shackle for locking the shackle when the
shackle is in the closed position and the projecting means being
receivable by notches in the peripheries of the tumblers for moving
the engagement means out of engagement with the short leg portion
of the shackle to unlock the shackle when the tumblers are set to
the opening combination.
12. A combination padlock as set forth in claim 11, wherein the
fence member is cooperable with means provided by the shifter plate
for preventing the opening combination of the padlock from being
changed when the shackle is in the combination-changing position
unless the tumblers are set to the opening combination.
13. A combination padlock comprising:
a body having an internal cavity;
a shackle having a long leg portion and a short leg portion, the
long leg portion being slidably supported by the body for enabling
the shackle to be moved from an open first position to a closed
second position;
a manually rotatable dial supported by the body;
a plurality of tumblers contained in the internal cavity, the
tumblers being rotatable by the dial;
a fence member having one end slidably connected to rail means
provided by the body, having engagement means near its other end
for engaging the short leg portion of the shackle, and having
projecting means, intermediate the one end and the engagement
means; and
a spring which acts against the fence member between the one end
and the projecting means for biasing the one end of the fence
member toward one end of the rail means and for biasing the
projecting means into contact with the peripheries of the
tumblers,
whereby the engagement means engages the short leg portion of the
shackle to releasably lock the shackle when the shackle is in the
closed position, the projecting means being receivable by notches
in the peripheries of the tumblers for moving the engagement means
out of engagement with the short leg portion of the shackle to
unlock the shackle when the tumblers are set to a predetermined
opening combination.
14. A combination padlock as set forth in claim 13, wherein the
engagement means comprises an opening in the fence member, the
opening being cooperable with a projection on the short leg portion
of the shackle for releasably locking the shackle in the closed
position.
15. A combination padlock as set forth in claim 13, wherein the
rail means comprises a wall and wherein the one end of the fence
member has a notch in its side in sliding engagement with the
wall.
16. A combination padlock as set forth in claim 13, wherein the
part of the fence member between the engagement means and the other
end is curved away from the short leg portion of the shackle when
the shackle is in the closed position.
17. A combination padlock as set forth in claim 13, wherein the
projecting means comprises a projecting rib formed in the fence
member.
18. A combination padlock as set forth in claim 13, further
comprising a ring disposed in the internal cavity and rotatable by
a key, the ring having means for moving the engagement means of the
fence member out of engagement with the short leg portion of the
shackle for unlocking the shackle when the ring is rotated in a
first direction by the key.
19. A combination padlock comprising
a body having an internal cavity;
a shackle having a long leg portion and a short leg portion, the
long leg portion being slidably supported by the body for enabling
the shackle to be moved between an open first position and a closed
second position;
a manually rotatable dial supported by the body;
a plurality of tumblers contained in the internal cavity, the
tumblers being rotatable by the dial;
locking means in the internal cavity for releasably engaging the
short leg portion of the shackle to releasably lock the shackle in
the closed position; and
a ring disposed in the internal cavity and rotatable by a key, the
periphery of the ring having gear teeth cooperable with teeth on
the key, the ring having means for moving the locking means out of
engagement with the short leg portion of the shackle for unlocking
the shackle when the ring is rotated in a first direction by the
key.
20. A combination padlock as set forth in claim 19, wherein the
ring includes means cooperable with means provided by the body for
limiting rotation of the ring in a second direction opposite the
first direction.
21. A combination padlock as set forth in claim 19, wherein the key
comprises a spline shaft.
Description
The invention relates to combination padlocks and is more
particularly directed to improvements in single dial combinations
padlocks of the type including means for setting or changing the
combination.
BACKGROUND OF THE INVENTION
Single dial combination padlocks of the type having means for
changing the combination are known. See, for example, U.S. Pat.
Nos. 2,090,631, 2,154,660, 2,330,447, 2,852,928, and 3,533,253.
However, these padlocks require either that the padlock be
partially disassembled or that a key or other tool be employed to
change the combination.
In U.S. Pat. No. 3,729,962, a combination padlock has tumblers with
rim and hub portions connected through a friction clutch type
connection. By actuating an externally mounted lever (movable only
when the shackle is in open position) the hubs may be rotated
relative to the rims by the dial for setting a combination of one's
own choice. The external lever of this padlock invites tampering
which may damage the combination-changing mechanisms. Furthermore,
because combination locks tempt persons to manipulate them before
becoming familiar with the written instructions which accompany the
lock, the combination may inadvertently be changed to a new
combination unknown to the user, particularly since the combination
is set with the shackle in the usual open position. The lock must
then be returned to the manufacturer who expends considerable
effort in opening it, if possible. Moreover, because the lever must
be manipulated with the fingers, the degree to which this prior art
device may be miniaturized is limited.
SUMMARY OF THE INVENTION
A primary object of the invention is to provide a combination
padlock which enables the combination to be changed without
disassembling the padlock and without using a key or other tool,
and which eliminates obstrusive means on the padlock for changing
the combination.
Another object of the invention is to provide a combination padlock
having an improved and simplified locking mechanism.
Still another object of the invention is to provide a combination
padlock having an improved mechanism for enabling the padlock to be
opened by a key in the event that the combination is forgotten.
A single-dial combination padlock made in accordance with the
invention comprises a body having an internal cavity and a shackle
of the usual type (i.e., having a long leg portion and a short leg
portion) mounted on the body so that the long leg portion extends
into the internal cavity. The shackle is movable to the usual open
first position and closed second position and is further movable to
a combination-changing third position. A plurality of tumblers in
the internal cavity are positionable by a manually rotatable dial
mounted on the body. A single floating fence member is cooperable
with notches in the peripheries of the tumblers for locking the
shackle in the closed position except when the tumblers are set to
the opening combination. When the shackle is moved from the usual
open position to the combination-changing third position, the
combination of the padlock may be changed merely by turning the
dial to the desired new combination.
The above-described objects and advantages of the invention, as
well as other objects and advantages, will be apparent from the
following detailed description of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further described in conjunction with the
accompanying drawings, which illustrate a preferred and exemplary
embodiment, and wherein:
FIG. 1 is a front elevational view of a combination padlock made in
accordance with the invention;
FIG. 2 is an enlarged front elevational view of the padlock with
the dial removed and with a key inserted in the padlock, this view
showing the padlock casing cut away and in cross section;
FIG. 3 is a transverse cross-sectional view taken approximately in
the plane of line 3--3 of FIG. 2;
FIG. 4 is a longitudinal cross-sectional view taken approximately
in the plane of line 4--4 of FIG. 2;
FIG. 5 is an enlarged perspective view of a fence member employed
in the padlock of FIGS. 1-4;
FIGS. 6-9 illustrate the various operating positions on the fence
member of FIG. 5 and associated parts of the padlock;
FIG. 10 is an exploded perspective view of the tumblers, tumbler
drivers, and combination-changing mechanism of the padlock of FIGS.
1-4;
FIGS. 11-14 illustrate the various operating positions of the
combination-changing mechanism of FIG. 10 and associated parts of
the padlock;
FIG. 15 is a rear elevational view of the padlock, this view
showing a keyhole in the casing;
FIG. 16 is a plan view of a key receivable by the keyhole shown in
FIG. 15 for opening the padlock; and
FIGS. 17 and 18 illustrate the operating positions of a bolt member
employed in the padlock, the bolt member being rotatable by the key
of FIG. 16 for unlocking the padlock without dialing the
combination.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, a single-dial combination padlock made
in accordance with the invention essentially comprises a body A, a
shackle B, a manually rotatable dial C, a plurality of tumblers
D1-D3, and a floating fence member E. A tumbler shifter assembly F
is provided to enable changing or setting the combination to a
combination of one's own choice. An annular bolt G rotatable by a
key H is provided for enabling the padlock to be opened without
dialing the combination, a condition which is dictated when one
forgets or loses the combination.
As shown in FIGS. 2-4, body A comprises a frame 10 enclosed in a
casing 11 which comprises a side wall 12, which may be cylindrical
as illustrated, having one end closed by a wall 13 for forming the
rear surface of the padlock. For convenience of manufacture and to
minimize the number of parts, it is preferred that the frame be
made by die-casting. As shown in FIGS. 3 and 4, the upper edge
portion 14 of side wall 12 is bent over sections 34, 36 and 38 of
an annular rim on the frame for securing the manually rotatable
dial C to the body. The dial is urged outwardly from the body by a
dial spring 16 comprising a coil spring which encircles hub portion
18 of the dial and which acts against shifter plate 48 of shifter F
(to be described later) to bias the upper surface of peripheral rim
20 of the dial against edge portion 14 of the casing. Inward
movement of the dial relative to body A is restricted by the
interaction of the bottom surface of rim 20 of the dial with
surfaces 22, 24, 26, and 28 of frame 10, shown best in FIG. 2.
Shackle B has the usual J-shaped configuration with the long leg
portion 40 extending through an opening 41 in casing side wall 12
and into a body cavity 45 enclosed by frame 10 and dial C, the long
leg portion being slidably supported by the frame for enabling the
shackle to be axially moved between the usual open and closed
positions. The short leg portion 43 of the shackle is received by
an opening 44 in casing side wall 12 when the shackle is in the
closed position. A stop wall 46 on frame 10 in alignment with
opening 44 limits movement of the shackle into the frame to the
closed position, as shown in FIG. 2. However, if the shackle is
rotated from the usual open position (see FIG. 7) to another
position so that the end of the short leg portion of the shackle
does not enter opening 44 of the casing when the shackle is pushed
into body A, the long leg portion of the shackle may be pushed
further into the body to a combination-changing position (see FIG.
13) to be subsequently described.
Referring to FIGS. 4 and 10, three annular gate tumblers D1, D2 and
D3 are supported centrally in the body cavity by a tumbler shifter
assembly F comprising the shifter plate 48 and a pair of spaced,
parallel side plates 50 and 52 carried by the shifter plate. As
shown in FIG. 3, dial spring 16 acts against the intermediate
portion of the shifter plate to bias a lug 54 at one end of the
plate against the sloping bottom surface 56 of a recess 57 (FIG. 2)
between rim sections 36 and 38 of the frame and to bias bent
portion 58 at the other end of the shifter plate into engagement
with surface 60 of a guide plate 62 which is carried in an annular
recess 64 in the long leg portion of the shackle. As shown in FIG.
2, the shifter plate is also held in position in the body cavity by
walls 65 and 66 of the frame. Referring to FIGS. 2 and 4, side
plates 50 and 52 have slots 67 and 68, respectively, which receive
lugs or ears 70 and 71 on the shifter plate, the lugs being movable
to a limited extent in the slots so as to enable the shifter plate
to "float" in the body cavity. Consequently, when dial C is turned,
teeth 72 on the dial hub 18 (see FIG. 4) produce a ratcheting sound
and feeling as they pass over a single tooth 73 on the shifter
plate (FIG. 10). Tooth 73 is slightly off center in relation to the
teeth 72 on the dial.
As shown in FIG. 4, wall 65 of the frame maintains the parallel,
elongated slots 74, 76 and 78 of side plate 50 in receiving
engagement with portions of the peripheral edges of gate tumblers
D1, D2 and D3, respectively, and wall 66 maintains similar slots
80, 82 and 84 of side plate 52 in receiving engagement with edge
portions diametrically opposite the portions received by the slots
of side plate 50. When shifter plate 48 is in its normal position,
shown in FIGS. 2-4, teeth 90 on the inner periphery of annular gate
tumbler D1 engage teeth 72 on dial hub 18 for enabling that gate
tumbler to be rotated with the dial C.
Annular gate tumblers D2 and D3 are identical in configuration to
gate tumbler D1, but are rotatable by associated driver tumblers 96
and 98, respectively. The driver tumblers are rotatably supported
on a shoulder 100 of a stud 102 provided by frame 10(FIG. 10), the
end of the stud being received by an opening 103 in dial hub 18, as
shown in FIGS. 3 and 4. The driver tumblers are axially spaced on
the stud by a center spacer 104. A second center spacer 106 carried
by the stud in a position between dial C and driver tumbler 96 is
cooperable with the bottom surface 108 of dial hub 18 for
maintaining the driver tumblers on the stud in the positions shown.
As shown in FIG. 4, a lug 114 projecting from surface 108 of the
dial hub is cooperable with an upturned lug 116 on driver tumbler
96 for enabling that driver tumbler to be positioned by dial C. A
downturned lug 118 on driver tumbler 96 is cooperable with an
upturned lug 120 on driver tumbler 98 for enabling driver tumbler
98 to be positioned by driver tumbler 96.
Referring to FIGS. 3 and 10, when shifter plate 48 is in the normal
position shown in FIGS. 2-4, gear teeth 110 and 112 on the outer
peripheries of driver tumblers 96 and 98, respectively, engage the
toothed inner peripheries 90 of annular gate tumblers D2 and D3,
respectively, for enabling those gate tumblers to be rotated with
the driver tumblers.
As shown in FIG. 10, each gate tumbler is provided with a notch 126
in its outer periphery. When shifter plate 48 is in normal
position, rotation of dial C to the three-number opening
combination in the usual manner positions the gate tumblers such
that the notches 126 are aligned for receiving a projection on the
fence member E, thereby unlocking the shackle in a manner to be
described subsequently. Each gate tumbler is further provided with
a downturned lug 122, of which lug 122 on gate tumbler D3 is
cooperable with a flag 124 on guide plate 62 (see FIG. 3) for
scrambling the combination when the shackle is pulled from body A
to the open position.
Referring to FIG. 5, the locking means or fence member E comprises
an elongated plate having a notch 130 in its side in end portion
131 of the plate, the notch receiving a wall or rail 132 on the
frame, as shown in FIGS. 2 and 8, for slidably connecting end
portion 131 of the fence member to the frame. A rectangular opening
134 near the opposite end portion 135 of the plate is cooperable
with a projection 136 on short leg portion 46 of shackle B for
releasably locking the shackle in the closed position, as shown in
FIGS. 2 and 9. End portion 135 of the fence member curves away from
the short leg portion of the shackle when the shackle is in the
closed position for reasons which will be described later. The
intermediate portion of the plate is formed to provide a projecting
rib 138 which is adapted to be received by notches 126 in the
peripheries of the gate tumblers D1-D3 when the tumblers are set to
the opening combination. As shown in FIGS. 2 and 3, a coil spring
140 has one end received by a recess 142 in frame 12 and receives
in its other end a stud 144 on the fence member between notch 130
and rib 138.
Fence member E is essentially a floating member which works as a
single- or double-acting lever on different occasions. Under
constant pressure from coil spring 140, end portion 131 of the
fence member is biased against the side of a rib or wall 146 formed
at one end of rail 132, while rib 138 of the fence member is biased
against the peripheries of gate tumblers D1-D3, as shown in FIGS.
2, 7 and 9. Because the fence spring 140 acts between the two
contact points 131 and 138, the fulcrum of the fence member's lever
action can be shifted to either of these two points.
Operation of fence member E will now be described with reference to
FIGS. 6-9. FIG. 9 shows shackle B in closed position wherein coil
spring 140 biases rib 138 of the fence member against the
peripheries of the gate tumblers (only gate tumbler D3 being shown)
and biases end portion 131 against the side wall 146, thereby
causing projection 136 of the short leg portion of the shackle to
be received in opening 136 of the fence member for locking the
padlock. Referring to FIG. 6, rotating dial C to the opening
combination of the padlock positions the gate tumblers such that
notches 126 in the peripheries of the gate tumblers are aligned for
receiving rib 138 of the fence member, thereby permitting spring
140 to pivot the fence member about its point of contact with wall
146 sufficiently to disengage projection 136 of the short leg
portion of the shackle from the opening 134 of the fence member.
The shackle can then be pulled out of body A to the usual open
position shown in FIG. 7. As the shackle is being pulled from the
body, flag 124 on guide 62 (shown best in FIG. 3) engages
downturned lug 122 on the bottom gate tumbler D3 for causing that
tumbler to be rotated to the position shown in FIG. 7, thereby
scrambling the combination. Because notch 126 of gate tumbler D3 is
moved out of receiving engagement with rib 138 of the fence member,
the fence member is returned to its locking position, as shown in
FIG. 7.
Referring to FIG. 8, as the shackle is pushed into the body to the
closed position for locking the padlock, the end of the short leg
portion of the shackle is brought into sliding contact with curved
end portion 135 of the fence member. The resulting camming action
causes the fence member to act as a double lever, pivoting about
its point of contact at 138 with the peripheries of the gate
tumblers, which causes notch 130 in the fence member to slide along
rail 132 of the frame against the force of spring 140. When the
shackle has been pushed in to the extent that the projection 136 on
the shackle reaches opening 134 in the fence member, spring 140
snaps the fence member into locking engagement with the shackle.
Further inward movement of the shackle relative to the body is
prevented by stop wall 46, shown in FIGS. 2, 6-9 and 13. The
arcuate path of the fence member during this action tends to pull
the shackle inward further than at its rest position when fully
engaged. This means that more spring compression is required at the
beginning of the exiting action of the shackle, which tends to hold
the shackle in against misuse of the lock.
The combination-changing feature will now be explained with
reference to FIGS. 2-4 and 10-14. Tumbler shifter assembly F,
comprising shifter plate 48 and spaced side plates 50 and 52 which
carry the gate tumblers, is actuated by long leg portion 40 of the
shackle for enabling the opening combination of the padlock to be
changed only when the shackle is in a particular
combination-changing position (see FIG. 13), which is different
from the usual open and closed positions of the shackle. When the
shackle is in the usual closed and open positions, dial spring 16
biases the bent end 58 of shifter plate 48 against surface 60 of
guide plate 62, as shown in FIGS. 3 and 12. With the shifter plate
in this position, side plates 50 and 52 support the gate tumblers
D1-D3 in engagement with their associated drivers (i.e., teeth 90
on gate tumbler D1 engage the teeth 72 of dial hub 18 and teeth 90
on gate tumblers D2 and D3 engage the peripheral teeth 110 and 112
of drive tumblers 96 and 98, respectively), and the padlock is
operated in the usual manner of a three-number single-dial
combination padlock.
When it is desired to change the opening combination to a new
combination, it is necessary that shifter plate 48 be pivoted about
its lug 54 to the position shown in FIG. 14 (and shown in phantom
at 48' in FIG. 3) for causing side plates 50 and 52 and the gate
tumblers D1-D3 to be shifted in directions parallel to the axis of
rotation of the gate tumblers for thereby disengaging the gate
tumblers from their associated drivers. The necessary pivoting
action of shifter plate 48 is accomplished by the following
procedure. Firstly, the padlock is opened by dialing the opening
combination and pulling shackle B from body A to the usual open
position shown in FIG. 7. Secondly, the shackle is rotated
180.degree. relative to the body and then pushed into the body to
the combination-changing position shown in FIG. 13, causing surface
60 of guide plate 62, which is carried by long leg portion of the
shackle, to be moved out of supporting contact with bent end 58 of
shifter plate 48. However, although the bent end 58 of the shifter
plate is now free, dial spring 16 cannot pivot the shifter plate
about lug 54 because a lug 150 (see FIG. 11) on the shifter plate
still rests upon side edge 152 of fence member E, which is in the
locking position as a result of the scrambling action explained
above. Therefore, for moving the fence member out of its supporting
relationship with lug 150 of the shifter plate, a third step is
required in which dial C is again turned to the opening
combination, thereby enabling spring 140 to move the fence member
to the position shown in FIG. 13 and permitting dial spring 16 to
pivot the shifter plate about its lug 54 to the
combination-changing position shown in FIG. 14, wherein bent
portion 58 of the shifter plate is biased into contact with long
leg portion 40 of the shackle. Fence member E is cut away at 154 so
as not to restrict the pivoting movement of the shifter plate to
this position. Referring to FIG. 2, as the shifter plate pivots, a
first pair of spaced guide ribs 65a and 65b on wall 65 of frame 10
and a second pair of spaced guide ribs 66a and 66b on wall 66 guide
the side plates 50 and 52, respectively, in directions parallel to
the axis of rotation of the gate tumblers D1-D3, so that the gate
tumblers are moved away from dial C along the axis of rotation,
thereby disengaging the gate tumblers from their associated drivers
(i.e., gate tumbler D1 is moved out of engagement with teeth 72 on
dial C and gate tumblers D2 and D3 are moved out of engagement with
drive tumblers 96 and 98, respectively). The opening combination of
the padlock may now be changed to a new combination by rotating
dial C in the usual manner to the desired new combination, which
alters the position of dial C relative to gate tumbler D1 and
alters the positions of driver tumblers 96 and 98 relative to gate
tumblers D2 and D3. To establish a new opening combination of
10-25-18, for example, the numbered dial C (FIG. 1) is turned
clockwise past number 10 twice and is stopped at this number the
third time around. Then, the dial is turned counterclockwise past
number 25 once and is stopped at this number the second time
around. Finally, the dial is turned clockwise and is stopped at
number 18. The shackle is then pulled outwardly from the body A,
which causes shifter plate 48 to be returned to its normal position
by the camming action of surface 62 of guide plate 60 with a
bent-up lug 156 on the shifter plate, shown in FIGS. 2, 10 and 13.
Side plates 50 and 52, carried by the shifter plate, therefore move
gate tumblers D1-D3 back into engagement with their associated
drivers. The combination padlock is then ready for use with the new
opening combination.
A key-actuatable bolt G is provided for enabling the padlock to be
unlocked by a key. Referring to FIG. 2, bolt G comprises an annular
member or ring supported by surfaces 160, 162 and 164 of frame 10.
A downturned lug 170 on the bolt abuts one side of a wall 172 on
the frame and a downturned lug 174 abuts end portion 131 of fence
member E for maintaining the bolt member in the rest position shown
in FIGS. 2 and 17. A key H(FIG. 16), preferably formed from a
spline shaft, has six teeth 177 equally spaced about its periphery,
the key being insertable in a keyhole 178 in the rear of the
padlock, shown in FIG. 15. As shown in FIG. 4, when the key is
inserted in the keyhole, shaft portion 176 of the key is received
by a cylindrical opening 179 in the wall 66 of the frame for
supporting the key with its teeth in engagement with gear teeth 180
on the inner periphery of bolt G. Rotation of the key in the
clockwise direction (as viewed in FIGS. 2, 17 and 18) rotates bolt
G in the clockwise direction, thereby causing downturned lug 174 of
the bolt to move end portion 131 of the fence member along wall 132
away from wall 146 against the action of spring 140. The fence
member is thus caused to pivot about the rib 138 for moving opening
134 of the fence member out of engagement with projection 136 of
shackle B, as shown in FIG. 18. With the fence member in this
position, the shackle may then be pulled from the padlock to the
open position. When the torque applied to the key is removed,
spring 140 moves end portion 131 of the fence member against
downturned lug 174 on the bolt for returning the bolt to the rest
position shown in FIGS. 2 and 17.
The configurations of bolt G and key H enable the bolt to be
rotated to an extent which cannot be accomplished by manipulation
of the bolt by a simple wire or rod inserted in the keyhole.
Although it might be possible to move a single tooth on the bolt in
this manner, release of the shackle requires that several teeth be
actuated against the tendency of fence spring 140 to return the
fence member and the bolt to their normal or rest positions. When
the bolt is in the rest position shown in FIGS. 2 and 17,
counterclockwise rotation of the bolt is prevented by downturned
lug 170 which abuts the one side of wall 172 of the frame.
Referring to FIG. 2, a second set of teeth 182 diametrically
opposite gearing 180 and a cylindrical channel 183 in wall 65
provide for a different key position and a different key
configuration, the key 184 (shown in phantom) having four teeth
equally spaced about its periphery.
It is believed that the advantages and improved results furnished
by the combination padlock of the invention will be apparent from
the foregoing description of a preferred embodiment of the
invention. Various changes and modifications may be made without
departing from the spirit and scope of the invention as sought to
be defined in the following claims.
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