U.S. patent number 3,710,603 [Application Number 05/184,521] was granted by the patent office on 1973-01-16 for key operable padlock with rotatable seal for plug.
This patent grant is currently assigned to Sargent & Greenleaf, Inc.. Invention is credited to Harry C. Miller.
United States Patent |
3,710,603 |
Miller |
January 16, 1973 |
KEY OPERABLE PADLOCK WITH ROTATABLE SEAL FOR PLUG
Abstract
A high security padlock having a padlock casing and a generally
U-shaped shackle. The casing has a central bore located between the
sockets to receive and removably house a key lock plug, operable by
a key slot in the bottom of the padlock body. A sealing cover
member forms an upper closure for the bore above the plug and
includes a pair of concave recesses which normally interfit with
surface portions of the shackle legs and also includes interlock
means displaced angularly from these recesses to interlock with the
main body portion when either of the shackle legs are located in
their associated sockets in the padlock body.
Inventors: |
Miller; Harry C. (Rochester,
NY) |
Assignee: |
Sargent & Greenleaf, Inc.
(Rochester, NY)
|
Family
ID: |
22677237 |
Appl.
No.: |
05/184,521 |
Filed: |
September 28, 1971 |
Current U.S.
Class: |
70/38A;
70/52 |
Current CPC
Class: |
E05B
67/24 (20130101); Y10T 70/459 (20150401); Y10T
70/489 (20150401) |
Current International
Class: |
E05B
67/00 (20060101); E05B 67/24 (20060101); E05b
067/24 () |
Field of
Search: |
;70/38R,38A,38B,38C,39,52,370,371 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Craig, Jr.; Albert G.
Claims
What is claimed is:
1. A padlock comprising a padlock casing having a bottom wall
portion, a main body portion, and an upper body portion, a U-shaped
shackle including a curved intermediate portion and a pair of
shackle legs, said casing having laterally spaced sockets opening
through said upper body portion for receiving the shackle legs and
accommodating axial reciprocative movement of the shackle between a
lower locking position and an upper release position, said main
body portion having a central bore therein located between said
sockets shaped to receive and removably house a key lock plug, a
key lock plug removably received in said bore including bolt means
movable into and out of locking engagement with said shackle legs,
said bottom wall portion defining the bottom of said bore and
having a key opening therein for projection of a key into said key
lock plug for operating the latter, a sealing cover member forming
an upper closure for said bore above said plug, said sealing cover
member including a cylindrical top portion of slightly greater
diameter than the spacing between the confronting surfaces of said
shackle legs and having a pair of diametrically opposite concave
recesses in the perimeter of said top portion registering with and
forming a portion of said sockets to receive confronting portions
of the shackle legs therein at a selected angular position of said
cover member, said cover member also including interlock means
displaced angularly from said concave recesses to interlock with
said main body portion when said concave recesses register with
said sockets in positions for receiving said shackle legs for
retaining said cover member against withdrawal from the padlock
casing when the shackle is in said lower locking position.
2. A padlock as defined in claim 1, wherein said key lock plug
includes a bolt operator projecting upwardly therefrom, and said
bolt means comprises a removable locking bolt member releasibly
coupled to said bolt operator.
3. A padlock as defined in claim 2, wherein said interlock means
includes lug formations projecting downwardly and outwardly from
said cylindrical top portion of said cover member and said main
body portion having internal arcuate lug recesses concentrically
bounding said bore and communicating with said sockets, the
outwardly projecting portions of said lug formations being movable
downwardly in said sockets when the shackle legs are withdrawn
therefrom and being angularly shifted into said arcuate lug
recesses to interlock the cover member in said bore and aline the
concave recesses with said sockets.
4. A padlock as defined in claim 3, wherein the upper body portion
of said padlock casing includes a shroud formation extending
upwardly from said main body portion to a top surface substantially
at the level of the uppermost portion of the shackle when the
shackle is in locking position, said shroud formation having a
cruciform recess extending downwardly from said top surface
defining a first slot elongated along the plane of the shackle for
wholly receiving the shackle in nested relation therein and
defining a second slot perpendicularly intersecting the first slot
and opening rearwardly through said upper body portion to receive a
pair of apertured hasp members therein in position for insertion of
the shackle through the apertures thereof.
5. A padlock as defined in claim 2, wherein said padlock casing has
a flat top wall surface through which said sockets open, said
shackle projecting from said top wall surface and having one leg
thereof slidably retained in said casing by removable means, and
said top portion of said cover member having a flat substantially
circular top surface located flush with said top wall surface when
the cover member is interlocked with said main body portion.
6. A padlock as defined in claim 2, adapted for use with a pair of
apertured hasp members disposed in abutting registered relation
having apertures for receiving the padlock shackle, the padlock
including a filler block formation including a cylindrical body
portion and a spherical dome-shaped upper portion, each filler
block portion having diametrically opposite concave recess channels
therein to receive confronting surface portions of the shackle legs
and adjacent portions of the curved intermediate portion nested
therein, the filler block formation substantially filling the space
between said shackle legs and having a diametrically extending
recess across the upper portion thereof along an axis perpendicular
to the plane of the shackle sized to snugly accommodate portions of
said hasp members directly below the shackle apertures therein.
7. A padlock as defined in claim 2, wherein the upper body portion
of said padlock casing includes a shroud formation extending
upwardly from said main body portion to a top surface substantially
at the level of the uppermost portion of the shackle when the
shackle is in locking position, said shroud formation having a
cruciform recess extending downwardly from said top surface
defining a first slot elongated along the plane of the shackle for
wholly receiving the shackle in nested relation therein and
defining a second slot perpendicularly intersecting the first slot
and opening rearwardly through said upper body portion to receive a
pair of apertured hasp members therein in position for insertion of
the shackle through the apertures thereof.
8. A padlock as defined in claim 1, wherein said padlock casing has
a flat top wall surface through which said sockets open, said
shackle projecting from said top wall surface and having one leg
thereof slidably retained in said casing by removable means, and
said top portion of said cover member having a flat substantially
circular top surface located flush with said top wall surface when
the cover member is interlocked with said main body portion.
9. A padlock as defined in claim 1, wherein said key lock plug
includes a bolt operator projecting upwardly therefrom, and said
bolt means comprises a removable locking bolt member releasibly
coupled to said bolt operator for angular movement about a vertical
axis having end portions projecting into said sockets within said
main body portion at a locking position thereof, and said shackle
legs having confronting notches receiving said end portions of said
locking bolt when the latter occupies said locking position.
10. A padlock as defined in claim 9, wherein said interlock means
includes lug formations projecting downwardly and outwardly from
said cylindrical top portion of said cover member and said main
body portion having internal arcuate lug recesses concentrically
bounding said bore and communicating with said sockets, the
outwardly projecting portions of said lug formations being movable
downwardly in said sockets when the shackle legs are withdrawn
therefrom and being angularly shifted into said arcuate lug
recesses to interlock the cover member in said bore and aline the
concave recesses with said sockets.
11. A padlock as defined in claim 10, wherein said padlock casing
has a flat top wall surface through which said sockets open, said
shackle projecting from said top wall surface and having one leg
thereof slidably retained in said casing by removable means, and
said top portion of said cover member having a flat substantially
circular top surface located flush with said top wall surface when
the cover member is interlocked with said main body portion by
interfitting of said lug formations in said arcuate lug
recesses.
12. A padlock as defined in claim 10, adapted for use with a pair
of apertured hasp members disposed in abutting registered relation
having apertures for receiving the padlock shackle, the padlock
including a filler block formation including a cylindrical body
portion and a spherical dome-shaped upper portion, each filler
block portion having diametrically opposite concave recess channels
therein to receive confronting surface portions of the shackle legs
and adjacent portions of the curved intermediate portion nested
therein, the filler block formation substantially filling the space
between said shackle legs and having a diametrically extending
recess across the upper portion thereof along an axis perpendicular
to the plane of the shackle sized to snugly accommodate portions of
said hasp members directly below the shackle apertures therein.
13. A padlock as defined in claim 10, wherein the upper body
portion of said padlock casing includes a shroud formation
extending upwardly from said main body portion to a top surface
substantially at the level of the uppermost portion of the shackle
when the shackle is in locking position, said shroud formation
having a cruciform recess extending downwardly from said top
surface defining a first slot elongated along the plane of the
shackle for wholly receiving the shackle in nested relation therein
and defining a second slot perpendicularly intersecting the first
slot and opening rearwardly through said upper body portion to
receive a pair of apertured hasp members therein in position for
insertion of the shackle through the apertures thereof.
14. A padlock as defined in claim 1, adapted for use with a pair of
apertured hasp members disposed in abutting registered relation
having apertures for receiving the padlock shackle, the padlock
including a filler block formation including a cylindrical body
portion and a spherical dome-shaped upper portion, each filler
block portion having diametrically opposite concave recess channels
therein to receive confronting surface portions of the shackle legs
and adjacent portions of the curved intermediate portion nested
therein, the filler block formation substantially filling the space
between said shackle legs and having a diametrically extending
recess across the upper portion thereof along an axis perpendicular
to the plane of the shackle sized to snugly accommodate portions of
said hasp members directly below the shackle apertures therein.
15. A padlock as defined in claim 1, wherein said interlock means
includes lug formations projecting downwardly and outwardly from
said cylindrical top portion of said cover member and said main
body portion having internal arcuate lug recesses concentrically
bounding said bore and communicating with said sockets, the
outwardly projecting portions of said lug formations being movable
downwardly in said sockets when the shackle legs are withdrawn
therefrom and being angularly shifted into said arcuate lug
recesses to interlock the cover member in said bore and aline the
concave recesses with said sockets.
16. A padlock as defined in claim 15, wherein said padlock casing
has a flat top wall surface through which said sockets open, said
shackle projecting from said top wall surface and having one leg
thereof slidably retained in said casing by removable means, and
said top portion of said cover member having a flat substantially
circular top surface located flush with said top wall surface when
the cover member is interlocked with said main body portion by
interfitting of said lug formations in said arcuate lug
recesses.
17. A padlock as defined in claim 15, adapted for use with a pair
of apertured hasp members disposed in abutting registered relation
having apertures for receiving the padlock shackle, the padlock
including a filler block formation including a cylindrical body
portion and a spherical dome-shaped upper portion, each filler
block portion having diametrically opposite concave recess channels
therein to receive confronting surface portions of the shackle legs
and adjacent portions of the curved intermediate portion nested
therein, the filler block formation substantially filling the space
between said shackle legs and having a diametrically extending
recess across the upper portion thereof along an axis perpendicular
to the plane of the shackle sized to snugly accommodate portions of
said hasp members directly below the shackle apertures therein.
18. A padlock as defined in claim 15, wherein the upper body
portion of said padlock casing includes a shroud formation
extending upwardly from said main body portion to a top surface
substantially at the level of the uppermost portion of the shackle
when the shackle is in locking position, said shroud formation
having a cruciform recess extending downwardly from said top
surface defining a first slot elongated along the plane of the
shackle for wholly receiving the shackle in nested relation therein
and defining a second slot perpendicularly intersecting the first
slot and opening rearwardly through said upper body portion to
receive a pair of apertured hasp members therein in position for
insertion of the shackle through the apertures thereof.
19. A padlock as defined in claim 1, wherein the upper body portion
of said padlock casing includes a shroud formation extending
upwardly from said main body portion to a top surface substantially
at the level of the uppermost portion of the shackle when the
shackle is in locking position, said shroud formation having a
cruciform recess extending downwardly from said top surface
defining a first slot elongated along the plane of the shackle for
wholly receiving the shackle in nested relation therein and
defining a second slot perpendicularly intersecting the first slot
and opening rearwardly through said upper body portion to receive a
pair of apertured hasp members therein in position for insertion of
the shackle through the apertures thereof.
Description
BACKGROUND AND OBJECTS OF THE INVENTION
The present invention relates in general to padlocks, and more
particularly to padlocks of either the exposed shackle or shrouded
shackle type, having key lock plugs and a special construction
permitting removal of the key lock plug and replacement with
another plug to permit use of the padlock with a different key.
Heretofore, key operated padlocks have ordinarily been constructed
in such a manner that the key lock plug is incorporated in the
padlock body during manufacture so that it cannot be replaced
without substantial destruction of the lock. However, it has been
recognized that it is desirable in some instances, and particularly
in connection with high security uses of padlocks, to provide for
removal of the key lock plug in some manner so that a key plug
designed for another key can be substituted to permit operation of
the lock by a different key. Customarily, such locks have been
constructed so as to permit removal of the key plug either by use
of a special change key, or by rotation of one or a pair of
retaining screws accessible in the socket or sockets which normally
receive the shackle legs, thus permitting change only when the lock
is unlocked, or by retraction of a split ring accessible in a
similar manner to operation of the retaining screw. Other key
operable padlocks have been constructed wherein an exposed cover is
mounted over the bore for the key lock plug, with the cover held to
the padlock body by rivets or similar fastening devices. However,
such a construction does not meet the requirements of high security
lock applications.
An object of the present invention is the provision of a novel key
operable padlock construction wherein the key lock plug is
removable from the padlock body or case in a special manner only
when the shackle has been completely removed from the case, thus
permitting substitution of a key lock plug designed for a different
key.
Another object of the present invention is the provision of a novel
key operable padlock construction wherein a rotatable cover or
sealing member located within the padlock body to seal the key lock
plug within the body has concave segments at diametrically opposed
locations designed to interfit with portions of both shackle legs
of the padlock shackle so as to prevent rotation of the cover or
sealing member from sealing position to release position except
when both shackle legs are removed from the padlock body.
In many uses of padlocks, the padlock is in an exposed position
such that a person seeking unauthorized entry into the space
secured by the padlock may attempt to saw through the shackle or
insert a tool between the hasp members and the lock to wedge or
chisel the lock open. A further object of the present invention,
therefore, is the provision of a novel padlock construction for
improving the security of such padlocks and enhancing their
resistance against such efforts to gain unauthorized entry. This
may be accomplished by providing a shrouded type padlock body
wherein a portion of the padlock body forms a shroud about the
shackle which denies direct access to the shackle by a saw or
wedging tool. In another form of the present invention, a padlock
of the exposed shackle type is provided with a cover adapter
forming a filler block which fills the space between the legs of
the shackle, except for a central recess portion which is sized to
interfit closely with parts of two hasp end portions adjacent the
shackle receiving apertures in the hasps. This adapter or filler
block member effectively fills the space within the shackle to
prevent insertion between the hasps and the lock of a tool for
wedging or chiseling the lock open and also makes it more difficult
to saw the lock open because the saw would have to go through part
of the adapter as well as the shackle.
Other objects, advantages and capabilities of the present invention
will become apparent from the following detailed description, taken
in conjunction with the accompanying drawings illustrating
preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is an exploded perspective view of an exposed shackle
padlock embodying the present invention;
FIG. 2 is a vertical transverse section view thereof taken along
the line 2--2 of FIG. 1;
FIG. 3 is a vertical section view thereof taken along the line 3--3
of FIG. 2;
FIG. 4 is a horizontal section view taken along the line 4--4 of
FIG. 3;
FIG. 5 is a horizontal section view taken along the line 5--5 of
FIG. 2;
FIG. 6 is a bottom view of the locking bolt;
FIG. 7 is a perspective view of the cover adapter having a shackle
filler block which may be employed with the padlock; and
FIG. 8 is a perspective view of a shrouded type padlock embodying
the present invention, with the shackle shown exploded
therefrom.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, wherein like reference characters
designate corresponding parts throughout the several figures, there
is illustrated in FIGS. 1 to 6 a form of padlock, indicated
generally by the reference character 10, which is of the exposed
shackle type. The padlock 10 comprises a padlock body 11 of
generally elliptical configuration in top plan view, having a top
surface 12 and a bottom surface 13. The padlock body 11 is
preferably a unitary casted body, formed for example of hardened
steel, and has a pair of closed bottom sockets or bores 14, 15
opening through the top surface 12 for receiving the legs of the
shackle 16. The sockets 14, 15 have slightly constricted entrance
portions 14a, 15a of cylindrical configuration defining downwardly
facing transition surfaces or shoulders 14b, 15b, spaced below the
top surface 12.
The shackle 16 is preferably in the form of a U-shaped rod of
hardened steel having a longer leg 17 and a shorter leg 18. The
longer leg 17 passes through the circular entrance opening 14a in
the top surface 12 into the socket 14 and extends a substantial
distance within the padlock body 11 toward the bottom surface 13.
The leg 17 is permitted a selected amount of axial and rotatable
movement relative to the padlock body 11, but is normally
restrained against withdrawal from the socket 14 by means of a pin
19 driven through an opening 11a in the padlock body into a pin
aperture 17b in the leg 17. An end of the pin 19 projects slightly
from a side of the leg 17 into the socket 14 below the shoulder 14b
in underlapping relation to the shoulder so that the shoulder 14b
will intercept the projecting end of the pin upon upward movement
of the shackle. The free end portion of the shorter leg 18 enters
through the circular entrance opening 15a in the top surface 12
into the closed bottom socket 15 in the padlock body, when the
shackle is in locking position. By this construction, the shorter
leg 18 of the shackle can be withdrawn from the padlock body 11
when the padlock is unlocked, and can be swung to an exposed
position by rotating the shackle 16 about the axis of its longer
leg 17, the abutment of the ends of pin 15 with shoulder 14b
defining the limit of this withdrawal movement. The U-shaped
shackle 16 also comprises the usual curved intermediate portion 20
extending between the legs 17 and 18, which serves as the portion
which engages the usual apertured hasps member or pair of hasps
members, as indicated at 21a and 21b, having apertures 22a and 22b
which are of a diameter closely approximating the diameter of the
shackle and are adapted to register with each other to receive the
shackle therethrough. The shackle legs 17 and 18 each have a notch
17a, 18a located within the padlock body when the shackle is in
locking position as the portion which engages the usual apertured
hasps member or pair of hasps members, as indicated at 21a and 21b,
having apertures 22a and 22b which are of a diameter closely
approximating the diameter of the shackle and are adapted to
register with each other to receive the shackle therethrough. The
shackle legs 17 and 18 each have a notch 17a, 18a located within
the padlock body when the shackle is in locking position and which
are disposed in the confronting or inwardly facing portions of the
shackle legs to receive nose portions of a rotatable locking bolt
24 as later described.
The padlock body includes a closed bottom lower central bore
portion 25 which communicates with the sockets 14 and 15 and is
shaped and sized to snugly accommodate a key lock plug 26 of
conventional construction, having a usual rotatable cylinder
therein, including a bolt actuator 26a, disposed at the upper end
of the plug 26 when the core is properly arranged in the padlock
body. The core of plug 26 also includes a key opening in the
downwardly facing end portion of the rotatable cylinder, indicated
at 26b in FIG. 2, located immediately above a key opening 27 in the
bottom surface 13 of the padlock body for insertion of the key into
the key opening of the plug cylinder and rotation of the key
through the appropriate arc to unlock the key lock. Since the
conventional key lock plug 26 usually has a pair of flat sides,
indicated at 26c, and a pair of concave arcuate ends, the central
bore 25 for the plug is either similarly shaped in horizontal
cross-section or is cylindrical over most of its height and has
flats at its upper end to embrace and hold the plug, as will appear
from FIG. 5.
Immediately above the lower central bore 25 is an enlarged upper
central bore portion 28 of cylindrical configuration having a
larger radius than the curved portions of the lower central bore
portion 25, for accommodating the rotatable locking bolt 24 and a
rotatable closure seal or cover 29 of generally cylindrical
configuration. The rotatable locking bolt 24, as will be apparent
from FIGS. 1, 2 and 6, has a downwardly extending boss formation
24a which is recessed to define a downwardly facing socket or well
24b having a radial extension and shaped to properly interfit with
the bolt actuator 26a of the key lock plug so as to be rotated by
the cylinder of the plug 26 when the latter is shifted to unlocking
position by the proper key. The locking bolt 24 also includes a
pair of diametrically oppositely projecting nose portions 24c and
24d which interfit into the notches 17a, 18a of the shackle legs
17, 18 when the key lock plug cylinder, and therefore the locking
bolt 24, are in locking position. Suitable arcuate recesses 30
extend radially outwardly in the walls of the upper bore 28 at the
level of the locking bolt 24 to accommodate rotary arcuate movement
of the locking bolt nose portions 24c, 24d from the locking
position to the unlocking position to free the shackle 16 for
withdrawal to its unlocking position.
The closure seal or cover member 29 fits downwardly over the
locking bolt 24 into the upper bore portion 28, in a manner similar
to a manhole cover. The closure seal 29 includes a cylindrical top
portion 29a which is of the same radius as the upper bore portion
28 and intercepts a portion of the sockets or bores 14, 15 for the
shackle legs. The cylindrical periphery 29b of the cylindrical top
portion 29a has a pair of diametrically opposed concave
interruptions 29c which complement the sockets 14 and 15 so that
the surfaces of the concave interruptions 29c form a continuation
of and complete the cylindrical walls defining the entrance
portions of the sockets 14 and 15. Extending downwardly from the
circular top portion 29a are a pair of locking lug formations 29d
having downwardly facing bottom surface portions which bear upon
the shelf or shoulder surfaces, indicated at 28a, defining the
bottom of the upper bore portion 28 to locate the top surface of
the cylindrical top portion 29a flush with the top surface 12 of
the padlock body. The locking lug formations 29d also include
outwardly projecting lugs 29d' extending beyond the cylindrical
periphery 29b to interfit into arcuate recesses 31 in portions of
the cylindrical surface bounding the upper bore portion 28
immediately adjoining the sockets 14, 15 in an angular direction in
which the locking bolt is rotated during movement to unlocking
position.
Before the shackle has been assembled in the padlock body, the key
lock plug 26 is inserted into the lower central bore 25 therefor,
after which the locking bolt 24 is fitted downwardly on the bolt
actuator portion 26a of the plug. The closure seal 29 is then
installed in the padlock body by lowering the same downwardly into
the upper bore portion 28 with the lugs 29d' disposed in the
sockets 14, 15 for the shackle legs, until the lugs 29d' bottom on
the shelf or shoulder recess 24a, whereupon the closure seal is
rotated in a clockwise direction as viewed in FIGS. 4 and 5 to
project the lugs 29d' into the recesses 31 and aline the concave
interruptions 29c in the periphery 29b of the closure seal with the
sockets 14, 15 so that they register with and form continuations of
these sockets. With the key lock in unlocked condition, wherein the
nose portions 24c, 24d of the locking bolt 24 are withdrawn from
the sockets 14, 15, the shackle legs 17 and 18 can be inserted into
the sockets 14, 15 until the longer leg 17 bottoms in its socket
14, and the pin 19 is then driven into the shackle aperture 17b to
restrain the shackle in the padlock body. The presence of the
longer leg 17 in its socket 14 in both the locking and unlocking
positions of the shackle prevents any rotation of the closure seal
29 from its sealing or closed position because the shackle leg 17
is interfitted in the concave interruptions 29c of the closure seal
which forms part of the socket 14.
In order to remove the key lock core or plug and replace it with
another core or plug for use with a different key, the pin 19 must
be driven into aperture 17b in shackle leg 17, so that the shackle
16 can be completely withdrawn from the padlock body. The closure
seal 29 can then be rotated to a position registering the lugs 29d'
with the sockets 14 and 15 and the closure seal withdrawn from the
padlock body. With the padlock body inverted, the locking bolt 24
and key lock plug 26 are withdrawn from the bore portions 25 and
28, and another key lock plug 26 may then be inserted into the
lower central bore 25. The locking bolt 24 is then reassembled onto
the bolt actuator 26a of the new plug, and the closure seal 29 is
inserted and interlocked in the padlock body in the same manner as
in the initial installation, after which the shackle 16 can be
reinserted in the sockets 14 and 15 and a new retaining pin 19
installed.
A modified version of the cover member is shown in FIG. 7, wherein
a filler block is combined with the cover member and is indicated
at 36. The member 36 includes a lower body portion 36a having a
cylindrical periphery and a pair of diametrically opposed concave
interruptions, described later which complete the cylindrical walls
defining the entrance portions 14a and 15a of the sockets.
Extending downwardly from the lower body portion 36a are a pair of
locking lug formations 36d having downwardly facing bottom surface
portions to engage the shelf or shoulder surfaces defining the
bottom of the upper bore portion 28, so as to properly locate the
lower body portion 36a in the padlock body. The locking lug
formations 36d also include outwardly projecting lugs 36d' which
extend beyond the periphery of the body portion 36a to interfit
into the arcuate recesses 31 in the padlock body immediately
adjoining the sockets 14, 15.
Extending upwardly from, and integrally formed with the lower body
portion 36a is a filler block portion 37a of generally cylindrical
configuration in its lower region, for example of the same diameter
as portion 36a, terminating in a somewhat dome-shaped upper portion
37b. The filler block portion 37a has a rectangular recess or kerf
37c extending diametrically entirely through the filler block
portion along a diametric axis perpendicular to the plane of the
shackles and sized to just accommodate the portions of the hasps
sections 21a, 21b which lie below the shackle openings 22a, 22b.
The diametrically opposite surfaces of the filler block portion 37a
along the diametric axis which parallels the plane of the shackle
16 is provided with a pair of concave recesses 37d sized to
interfit with the confronting shackle portions and nestingly
receive the adjacent portions of the shackle to thereby fill all of
the region lying between the shackle legs 17, 18 and below the
curved top portion 20 of the U-shaped shackle 16 other than those
portions filled by the lower hasps sections.
It will be apparent that the presence of the filler block portion
37a and 37b filling the region between the shackle legs 17, 18 when
the shackle is in closed position will form an additional barrier
which provides a much greater amount of material which must be
sawed through if one attempts to make a saw cut through the shackle
to gain unauthorized access to the enclosure secured by the lock
and the close nesting relation of the adapter 35 with the hasps
portions in its recess 37c makes it more difficult to insert a
wedging tool between the hasps and lock to wedge or chisel the lock
open.
Still further protection is afforded by providing a shrouded
padlock body as illustrated at 40 in FIG. 8, wherein the body
includes a shroud portion 41 extending above the normal level of
the padlock body provided with a generally cross-shaped recess 42
for receiving the shackle therein so that the top of the curved
portion 20 of the shackle can be located level with or immediately
below the level of the top surface 43 of the shrouded portion of
the padlock body. The hasps portions 21a, 21b to be secured by the
shackle 16 may be introduced through the rearwardly opening portion
44 of the recess. The construction of the shrouded padlock is
otherwise the same internally as the padlock construction of the
embodiment of FIGS. 1 to 6, except that the pin 19 is omitted so
that the shackle can be wholly withdrawn from the padlock body when
the locking bolt 24 is in unlocking position. If desired, the two
shackle legs may be the same length in this embodiment. In the
embodiment illustrated, the front wall of the shrouded type padlock
body 40 is provided with a central recess 45 for receiving the end
of a chain, indicated at 46, and is provided with a pair of small
flanking recesses 47, together with drilled openings 48 extending
between the recesses 47 and intersecting the upper portion of the
recess 45 to receive a drive pin therethrough to be driven through
the drilled openings 48 and a link of the chain 46 for coupling the
padlock body 40 to the door or other security closure by means of
the chain.
* * * * *