Information
-
Patent Grant
-
6540273
-
Patent Number
6,540,273
-
Date Filed
Wednesday, January 3, 200124 years ago
-
Date Issued
Tuesday, April 1, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Carella Byrne Bain Gilfillan Cecchi et al.
- Gilfillan, III.; John G.
- Squire; William
-
CPC
-
US Classifications
Field of Search
US
- 292 315
- 292 307 R
- 292 314
- 292 317
- 292 319
- 292 318
- 292 321
- 292 323
- 292 324
- 292 325
- 292 326
- 292 307 A
- 292 307 B
- 024 115 L
- 024 136 A
- 024 136 L
- 188 651
- 188 67
-
International Classifications
-
Abstract
One end of a stranded steel cable is attached to a cast zinc seal housing having a chamber in which a steel sleeve with a tapered bore is positioned. The sleeve in one embodiment is fixed to the housing in the chamber or may be displaceable and captured in the chamber in a further embodiment. A serpentine clip locking member captured in the housing chamber resiliently radially grips the a second end of the shackle inserted into the sleeve bore and wedges and locks to the cable and sleeve when the shackle is withdrawn. The sleeve precludes damage to the softer zinc housing by the locking member when the locking member is displaced in the housing chamber. Various embodiments are disclosed. In a further embodiment, the one end of the cable exits the housing in a plane different than where the second end enters the chamber to enhance ease of insertion of the second end into engagement with the locking member.
Description
This invention relates to seals that comprise a body to which an end of a shackle, e.g., a solid or stranded steel cable, is attached, the free end being used to secure an article and the like. The free end is inserted into the seal for locking engagement with a locking collet in the seal, the free end for passing through the collet and seal and wedge locking to the collet and body in the withdrawal direction.
Of interest are commonly owned U.S. Pat. Nos. 5,582,447 ('447), 5,222,776 and 5,820,176, all relating to security seals and locks and which are incorporated, by reference herein in their entirety.
Each of the above patents generally disclose seals relating to the seal disclosed herein. In particular, the '447 patent is of particular interest. This patent discloses a serpentine clip which forms a locking collet, made of steel or other materials which is located in a tapered bore of a housing. One end of a stranded cable is secured and locked to the housing by a first clip in a first tapered bore of the housing or may be swaged to the housing in the housing first bore. The seal has a second bore which is tapered and in which a second clip collet is located. When a cable or wire is inserted into the second tapered bore and through the second collet, the collet resiliently grips the cable or wire and displaces with it as the cable is withdrawn. The collet and tapered.bore permit any length of cable or wire to be inserted therethrough in the insertion direction which is toward the larger end of the tapered bore. The larger bore end permits the collet to expand and let the cable or wire slip therethrough.
Any attempt to withdraw the cable or wire pulls the collet therewith wedging the collet against the narrow end of the tapered bore, locking the collet to the cable or wire and to the housing. This housing is disclosed as comprising hardened metal or plastic, but in current practice preferably comprises die cast zinc.
However, thermoplastic material or zinc are not generally as strong as hardened steel and may not survive the rigors of use, especially tampering attempts in which the cable or wire is repetitively pulled back and forth to displace the collet therewith and defeat the seal. This action may cause the reciprocating clip collet to damage the seal housing internally and diminish the integrity of the seal. Also, evidence of such tampering attempts are not readily apparent from external observation of the locked seal.
The other patents noted above disclose similar security seals employing balls as the locking elements instead of the locking clip collet of the '447 patent.
The present inventor recognizes a need for a seal such as disclosed in the '447 patent discussed above, but which preferably uses other materials such as zinc. However, since these other materials are not as resistant to damage as steel, use of such materials may not be as desirable for this type of seal.
A seal according to the present invention comprises a housing made of a first material and having a first chamber with opposing first and second ends, the housing having an opening in communication with the ambient atmosphere and the chamber at least the chamber first end. A sleeve is in the chamber and has a tapered bore in communication with the opening and made of a second material different than the first material, the bore tapering in a first direction from a large transverse dimension adjacent to the chamber second end to a relatively smaller transverse dimension adjacent to the first chamber first end. A shackle has a free end for insertion into the sleeve tapered bore through the opening in an insertion direction opposite the first direction. A locking member with a bore is located in the first chamber, the locking member for receiving and for gripping the shackle passing through the locking member bore, the locking member being free to displace with the shackle in the first chamber and tapered bore and being arranged to wedge against the sleeve and shackle in the tapered sleeve bore when the shackle is displaced in the first direction.
In one aspect, the second material is stronger than the first material.
In a further aspect, the second material is harder than the first material.
In a further aspect, the sleeve is dimensioned to be fixed in place in the housing first chamber. Preferably the sleeve is made of steel. In a further aspect, the sleeve has a length dimension and has a slit along the length dimension so that the sleeve is radially resilient.
In a further aspect, the housing first chamber is tapered, the sleeve having an external surface that is complementary to the housing first chamber taper.
Preferably the locking member is serpentine.
In a further aspect, the sleeve bore defines an axis, the locking member comprising a plurality of interconnected U-shaped loop members extending along the axis.
In a further aspect, the housing is at least one of plastic and zinc, the locking member is steel, and the sleeve is steel.
In a further aspect, the sleeve has a length between said chamber ends smaller than the chamber length between the chamber ends, the chamber having a transverse dimension relative to the sleeve outer dimension so that the sleeve can displace in the chamber with the locking member and shackle wedged to each other in response to displacement of the secured shackle in a direction opposite the first direction.
In a further aspect, the sleeve has an outer peripheral surface, and wherein the sleeve tends to displace in the chamber in response to insertion of the shackle therein, further including means for securing the sleeve in the chamber in fixed position to restrain the displacement of the sleeve in response to said insertion. In a further aspect, the means for securing the sleeve includes staking means for staking the sleeve to the housing.
In a further aspect, a seal according to an embodiment of the present invention comprises a housing having first and second ends lying in spaced parallel planes, the housing having a first chamber terminating at the second end at a first opening in communication with the ambient atmosphere and a second chamber terminating at a third housing end at a second opening in communication with the ambient atmosphere, the second opening being medial the spaced parallel planes. A shackle having a third end is secured to the housing in the second chamber and has a free end exiting the second chamber through the second opening, the free end for insertion into the housing first chamber through the first opening in an insertion direction. A locking member with a bore is located in the first chamber, the locking member for receiving and for gripping the shackle passing through the locking member bore, the locking member and chamber being arranged to wedge the locking member in the chamber when the shackle is displaced in a withdrawal direction opposite the insertion direction.
IN THE DRAWING:
FIG. 1
is a side elevation view of a seal according to an embodiment of the present invention;
FIG. 2
is an end view of the seal of
FIG. 1
;
FIG. 3
is an end view of the seal of
FIGS. 1 and 2
taken at an end opposite the end of
FIG. 2
;
FIG. 4
is an elevation view partially in section of the seal of
FIG. 1
;
FIG. 5
is a side elevation sectional view of the sectional portion of the seal of
FIG. 3
without the locking member in place;
FIG. 5
a
is a side elevation view of a second embodiment of a sleeve for use with the seal housing of
FIG. 4
;
FIG. 5
b
is a fragmented sectional end view of the sleeve of
FIG. 5
a;
FIGS. 6
a
and
6
b
are respective opposing end elevation views of the locking member of
FIG. 7
a;
FIGS. 7
,
7
a
and
7
b
are respective different side elevation views of the locking member of the embodiment of
FIGS. 4 and 5
;
FIGS. 8-10
are views similar to
FIG. 4
showing various stages of assembly of the shackle to the seal;
FIG. 11
is an elevation fragmented view partially in section of a further embodiment of a sleeve, locking member and housing;
FIG. 12
is a side elevation view of the sleeve of the embodiment of
FIG. 11
;
FIG. 12
a
is an end elevation view of the sleeve of
FIG. 12
;
FIG. 13
is a view similar to that of
FIG. 11
showing a further embodiment of a sleeve for use with a locking member and housing;
FIGS. 14 and 14
a
are respective side and end elevation views of the sleeve of
FIG. 13
;
FIGS. 15-17
are side elevation fragmented partially in section views of a sleeve, locking member and housing according to a further embodiment in various stages of assembly of the shackle to the seal;
FIGS. 18 and 18
a
are respective side elevation sectional and end elevation views of the sleeve of
FIGS. 15-17
;
FIGS. 19 and 20
are respective side elevation sectional and end elevation views of a sleeve according to a further embodiment;
FIG. 21
is a side elevation sectional view of a sleeve according to a further embodiment;
FIG. 22
is a side elevation sectional view of a sleeve according to a further embodiment;
FIG. 23
is an end elevation view of the seal of
FIG. 24
taken along lines
23
—
23
;
FIG. 24
is a side elevation view of a seal according to a further embodiment of the present invention;
FIG. 25
is a bottom plan view of the seal of
FIG. 24
;
FIGS. 26 and 27
are side elevation views of the seal of
FIG. 25
taken long lines
26
—
26
;
FIGS. 28
,
29
and
30
illustrate various stages of assembly of the hackle;
FIG. 31
illustrates the problem with employing a housing configuration similar to that of the embodiment of
FIG. 1
wherein the mass of the housing is reduced; and
FIG. 32
is a sectional elevation view of the embodiment of
FIG. 1
in the locked stage.
In
FIG. 1
, seal and lock assembly
10
comprises a seal and lock
12
to which is permanently secured a shackle
14
which preferably comprises stranded steel cable and may be other materials as desired for a given implementation, e.g., plastic or other metals, solid or stranded, including wires or filaments. The lock
12
includes a housing
16
which may be constructed as described and shown in the aforementioned patents in the introductory portion, and preferably as disclosed in the '447 patent. However, the preferred embodiment of the housing is as disclosed hereinafter. Modifications of the housings in the aforemtentioned patents should be made to meet the requirements of the present invention as described below.
In
FIG. 4
, the housing
16
, which is preferably cast zinc, has two chambers
18
and
20
. The housing also has a bore
19
which serves to reduce the amount of material used to form the housing
16
to reduce cost. One end
22
of the cable shackle
14
is secured to the housing
16
in the chamber
18
as by swaging or staking for example. In the alternative the end
22
may be locked to the chamber
18
in a manner similar to that disclosed in the '447 patent using a locking collet member as will be described below.
The second chamber
20
, in the embodiment of
FIG. 5
, is partially tapered, and preferably frusto-conical, in portion
24
and circular cylindrical in portion
26
. The length of chamber
20
portion
24
may be about 88% of the axial length of the chamber
20
. The circular cylindrical portion
26
has a diameter about the same as the larger diameter end of portion
24
. Portion
26
may also taper to an even larger diameter in the alternative, if desired.
A reduced diameter through hole
30
is at the smaller diameter end of the chamber
20
, and may be circular cylindrical. Hole
30
is sufficiently large to receive the shackle
14
therethrough. Hole
30
is smaller in diameter than the smallest diameter of the chamber
20
at the hole
30
end
32
of the chamber
20
. End
34
of the chamber
20
opposite end
32
is partially enclosed by swaged over thin wall portion
36
of the housing
16
. A second reduced diameter hole
38
of about the same diameter as hole
30
is formed in portion
36
. Holes
30
and
38
are aligned concentrically on axis
28
.
Located in the chamber
20
is a preferably steel sleeve
40
. The sleeve
40
extends for an axial extent smaller than portion
24
, e.g., about 86% of the length of portion
24
. Sleeve
40
is thin walled and has an internal tapered bore
42
and an external tapered outer surface. Preferably the inner and outer tapers are frusto-conical. The sleeve
40
bore
42
and outer surface has two portions
42
′ and
42
″. Portion
42
′ extends for a major length of the sleeve, e.g., about 90%. The external peripheral surface is complementary to and closely received in the chamber
20
tapered portion
24
. Bore portion
42
′ has an external peripheral surface that is has a more gradual taper than portion
42
″. However, the sleeve
40
does not wedge in the chamber
20
smaller diameter end or portion
24
and can be displaced axially therefrom toward end
34
of the housing chamber
20
. The sleeve internal bore
42
has a diameter at end
32
that is about the same as the diameter of the hole
30
.
In
FIG. 5
b
, a portion of sleeve
40
′ is shown wherein the sleeve
40
′ in an alternative embodiment, has a plurality of annularly spaced radially outwardly extending notches
41
. The notches distort the material forming radially outwardly extending projections
43
. The notches
41
and projections
43
are formed at the large diameter end
53
,
FIG. 5
a
, of the sleeve while the sleeve is in the bore
20
of the housing
16
, FIG.
4
. These projections
43
are in the form of rounded raised bumps. The projections
43
lightly stake the sleeve
40
′ to the housing
16
at the chamber
20
larger end to secure the sleeve
40
′ to the housing
16
in fixed position in the preferred embodiment. This position is the position of the sleeve
40
in FIG.
5
.
A serpentine shaped collet clip locking member
44
is in the chamber
20
and in the bore
42
of the sleeve
40
. The member
44
is shown in more detail in
FIGS. 6
a
,
6
b
,
7
,
7
a
and
7
b
. The member
44
comprise a plurality of legs
46
,
48
,
50
,
52
,
54
and
56
which extend in a generally similar direction relative to a central axis
59
. Legs
54
and
56
are inclined toward axis
59
and toward legs
52
and
46
, respectively. The adjacent legs are joined at their ends by arcuate end portions
47
,
49
an
51
and so on. Legs
46
and
48
and portion
47
form a U-shaped loop. Similarly, legs
50
and
52
and end portion
49
form a U-shaped loop as does legs
54
and
56
and end portion
51
and so on. Legs
48
and
50
terminate adjacent to each other and are also approximately parallel to each other. The legs and end portions extend about axis
59
and generally along this axis, and in practice may be inclined relative to each other and/or to the axis. The legs and end portions in end view,
FIGS. 6
a
and
6
b
, form a ring. Various embodiments of the member
44
are described in greater detail in the aforementioned '447 patent incorporated by reference herein. Reference is made to that patent for variations in the member
44
construction and materials. In this embodiment, the member
44
is steel solid wire. The member
44
resembles a paper clip somewhat, but in ring shape with multiple loops that extend about the axis
59
. The legs of member
44
are radially resilient and resiliently compressively engage the shackle
14
,
FIG. 4
, gripping the shackle when it engages and is received in the bore of the member
44
.
In
FIG. 4
, the locking member
44
is in the sleeve, both the locking member
44
and the sleeve
40
are in the chamber
20
. The locking member
44
has an outer diameter smaller than the inner diameter of the chamber
20
portion
26
, FIG.
5
. The member
44
can axially displace partially into the chamber
20
portion
26
externally the sleeve
40
along the axis
28
to the left in the figure (as illustrated in
FIG. 15
in another embodiment).
In operation, in
FIG. 8
, the free end
58
of the shackle
14
is passed through the chamber
20
and through the sleeve bore
42
and exits the housing
16
hole
38
(FIG.
5
). The shackle
14
also passes through the locking member
44
bore. The bore of the member
44
is sufficiently smaller than the outer diameter of the shackle
14
so as to resilient grip the shackle. This action is described more fully in the '447 patent. The friction grip of the member
44
to the shackle causes the member.
44
to displace toward end
34
of the chamber
20
, FIG.
8
. The swaged over housing portion
36
captures the locking member
44
in the chamber
20
as seen in
FIG. 8. A
portion of the member
44
is also in the sleeve bore portion
24
,
FIGS. 5 and 8
. The sleeve
40
bore in portion
24
at its larger diameter nearest end
34
of the chamber
20
is larger than the member
44
outer diameter. The sleeve smaller diameter end of portion
24
and portions
24
′ are smaller than the member
44
outer diameter.
During insertion of the shackle
14
in the insertion direction
60
,
FIG. 8
, the shackle pulls the locking member
44
also in direction
60
. In some implementations, the locking member
44
also may grip the sleeve
40
somewhat and pull the sleeve
40
therewith as well. This is not desirable at the sleeve restricts the radial opening of the member
44
upon pulling of the shackle therethrough. This may make insertion of the cable difficult. Therefore, it is preferable that the sleeve
40
remain in the rightmost position of
FIG. 4
during insertion of the shackle.
This retention of the sleeve in the position of
FIG. 4
during insertion is provided by notches
41
and burrs
43
or similar projections. The notches
41
stake the sleeve slightly to the housing in chamber
20
preventing the sleeve
40
from displacing to the left in the figure during insertion of the shackle end
58
in direction
60
. With the sleeve so staked, the insertion of the shackle through the member
44
pulls the member
44
to the left in the figure toward the larger diameter portion of the chamber
20
and partially clear of the sleeve. The member
44
in this position, can freely expand radially to permit the shackle to be pulled easily through the member
44
, although the member
44
exerts some radial resilient load on the shackle at this time. The staking may be optional depending upon the relative dimensions of the various components in certain implementations.
Once the shackle is inserted into the chamber
20
and member
44
and passes through the housing bore
38
, the shackle can no longer be withdrawn in direction
55
, FIG.
9
. When the shackle
14
is pulled in the withdrawal direction
55
,
FIG. 9
, the member
44
is pulled with the shackle in this direction. This action wedges the clip member
44
against the shackle
14
and against the sleeve
44
inner surface. The shackle is locked in place and can not be further withdrawn.
When the shackle
14
is displaced in the insertion direction
60
,
FIG. 10
, the locking member
44
being wedged attached to the shackle and to the sleeve
40
, may cause all three elements to displace in the insertion direction
60
. This is especially if the sleeve is not staked in place. If the sleeve is staked sufficiently in place, then the shackle, member
44
and shackle can not displace in direction
60
.
Without staking of the sleeve, the sleeve is free to displace in direction
60
. This is because the chamber
20
portion
24
is dimensioned to permit this relative motion and since the sleeve is not dimensioned to wedge clamp to the housing in chamber
20
. The cable shackle is now free to displace in both directions
58
,
FIG. 9
, and
60
,
FIG. 10
, a small distance.
Should a tamperer attempt to withdraw the shackle in direction
55
,
FIG. 9
, this will cause the sleeve to catch somewhat against the housing in the bore and provide resistance to displacement in the direction
60
. Any attempt to displace the shackle later can detect this resistance and provide evidence of an attempt at tampering and thus result in a closer examination of the seal to determine if the integrity of the seal was compromised. However, it is preferred that the sleeve
40
be staked to the housing rather than float in the housing chamber. This provides ease of insertion of the cable shackle in this embodiment even though tamper evidence is reduced accordingly. The tamper evidence is provided by the wedged locked engagement of the cable, collet locking member
44
and the sleeve to the housing when the sleeve is permitted to otherwise float in the housing chamber.
The preferably steel sleeve does not damage the housing
16
in the chamber
20
in those cases where the sleeve is not fixed in position, i.e., by staking. This is because the exterior surface of the sleeve is smooth and does not injure the interior chamber surface should the sleeve be displaced in the chamber. Thus the locking member
44
and sleeve in certain embodiments without staking of the sleeve to the housing can float in the chamber
20
. Such floating is not desirable in the present embodiment in that the locking member may become stuck in the sleeve in a relative position where the locking member can not readily radially displace outwardly during insertion of the cable and thus interferes with the insertion of the shackle making this more difficult.
The seal construction described advantageously permits a relatively soft material housing such as zinc to be used than otherwise, possible without the sleeve
40
. Thus low cost plastic and zinc housings can be used while providing enhanced security with this type of locking arrangement. The sleeve
40
enhances the utility of the assembly
10
without a detrimental reduction in security.
However, the problem of the floating sleeve can also be avoided without staking the sleeve by relative dimensioning of the housing chamber, sleeve and locking member in further embodiments. As long as the locking member can radially expand during insertion of the cable, then it does not matter if the sleeve is fixed in place or displaces. If the sleeve does displace, the end edge of the sleeve will stop when it reaches end
34
of the chamber
20
, FIG.
4
. At this point, the locking member and cable can be further displaced in the insertion-direction
60
, FIG.
8
. They are displaced to a point where the locking member has room to expand within the sleeve whose bore is sufficiently large to permit such expansion at this location in the sleeve. Such radial expansion of the locking member permits the cable to be further displaced relative to.the locking member. In this case, the sleeve when displaced in the withdrawal direction
55
,
FIG. 9
, may become slightly wedged to the chamber. This slight wedging shows withdrawal of the shackle and an attempt at tampering can be made by feel of a person tugging on the shackle cable in the insertion direction
55
.
A zinc body forming the housing
16
is ductile. This material does not permit ease of sliding motion of the locking collet member
40
in the housing chamber. Therefore, the steel sleeve permits the locking member
40
to slide therein more easily than in a zinc housing chamber with direct contact between the two materials. The softer ductile zinc material may also permit the displacing locking member to dig into the housing in the chamber and build up material in front of the locking member preventing it.from displacing during insertion of the shackle cable.
In
FIG. 11
assembly
64
comprises housing.
66
having a chamber
68
. The housing has two openings
70
and
72
in communication with the chamber
68
. Chamber
68
is circular cylindrical. A preferably steel sleeve
74
is in the chamber
68
. The sleeve may be press fit in place, staked in place or may float axially in directions
58
and
60
in chamber
68
according to a given implementation. Preferably the sleeve is in fixed position.
The sleeve
74
,
FIGS. 11
,
12
and
12
a
, has a tapered bore
76
and a like tapered outer surface
78
. The tapers may be frusto-conical for at least a portion of the bore
76
up to point
80
. The tapered portion of the bore
76
terminates at point
80
of bore
76
. At point
80
, the bore
76
terminates in a smaller diameter restricted bore
82
that is circular cylindrical. A radially outwardly extending flange
84
is at the smaller bore
82
end of the sleeve. The flange radially supports the sleeve
74
in the cylindrical housing chamber
68
. The sleeve if not staked or press fit in place, may be free to displace axially in the chamber
68
. The sleeve
74
at end
75
of the chamber
68
has its greatest diameter and is spaced from end
75
. This spacing provides room for a portion of the locking member
44
′. This position of the locking member permits the locking member to radially expand outwardly when the cable
14
is inserted in the insertion direction
60
permitting the cable
14
to slide within the bore of the locking member
44
′ and out of the housing chamber through opening
72
to the position shown. The locking member
44
′ and cable
14
are wedge secured to the sleeve
74
by pulling of the cable in the withdrawal direction
55
. Once wedged together they no longer can be separated by manipulation of the cable.
In
FIG. 13
, assembly
84
comprises housing
86
having a chamber
88
. The housing has two opposing end openings
90
and
92
in communication with the chamber
88
. Chamber
88
is circular cylindrical. A preferably steel sleeve
118
is in the chamber
88
. The sleeve
94
,
FIGS. 13
,
14
and
14
a
, has a tapered bore
96
and a circular cylindrical outer surface
98
. The outer surface
98
is complementary to the chamber
88
inner cylindrical surface. The sleeve
94
may be press fit in place, staked in place in the chamber
88
or it may float depending upon a given implementation and dimensions of the elements. The sleeve bore
96
taper is preferably frusto-conical for at least a portion of the bore
96
up to point
100
. The frusto-conical portion of the bore
76
terminates at point
100
of bore
96
. At point
100
, the bore
96
tapers at a more inclined frusto-conical taper
104
relative to the axis
102
. The bore
96
terminates in a smaller diameter restricted bore
106
that is circular cylindrical. The sleeve
94
bore
96
has it widest diameter
108
spaced from end
110
of the cylindrical portion of the housing
86
chamber
88
. This spacing permits a portion of the locking member
44
″ to enter this region and expand to permit the cable
14
to be inserted easily through the bore of the locking member
44
″, the sleeve
94
being fixed in place in this embodiment. The locking member and cable are secured wedged in place to the sleeve
94
by pulling the cable in the withdrawal direction
55
and can not be separated by manipulation of the shackle cable.
FIGS. 15-18
a
illustrate a further embodiment in which the sleeve
118
axially floats in the housing chamber
112
. In
FIG. 15
, assembly
108
comprises housing
110
having a chamber
112
. The housing
110
has two opposing end openings
114
and
116
in communication with the chamber
112
. Chamber
112
has a first circular cylindrical portion
112
′,
FIG. 17
, a second larger diameter circular cylindrical portion
112
″ and a third tapered preferably frusto-conical portion
112
′″,
FIGS. 15 and 16
. The cylindrical portion
112
′ is the smallest diameter and portion
112
″ is the largest diameter.
A preferably steel sleeve
118
is in the chamber
112
. The sleeve
118
,
FIGS. 18 and 18
a
, has a tapered bore
120
and a circular cylindrical outer surface
122
. The outer surface
122
is complementary to the chamber
112
inner cylindrical surface in portion
112
′, but is free to axially displace in and out of portion
112
′. The sleeve
118
floats axially in directions
55
and
60
, the respective withdrawal and insertion directions, in the chamber
112
in all of the portions
112
′,
112
″ and
112
′″. The sleeve bore
120
taper is preferably frusto-conical for at least a portion of the bore
120
up to point
124
. At point
124
, the bore
120
tapers at a more inclined frusto-conical taper
126
relative to the axis
128
. The bore
120
terminates in a smaller diameter restricted bore
130
that is circular cylindrical.
The sleeve
118
,
FIG. 15
, at the time of insertion of the cable
14
, is located entirely within the chamber
112
cylindrical portion
112
′. Thus the sleeve
118
has it widest diameter
132
end spaced from the junction
134
between the chamber
112
cylindrical portion
112
″ and the tapered portion
112
′″. The locking member
44
′″ is partially in the bore
120
of the sleeve
118
and almost entirely in the tapered chamber portion
112
′″. As the cable
14
is inserted in direction
60
, it pulls the locking member
44
′″ to the left in the figure into the housing chamber portion
112
″. This is the largest diameter of the chamber
112
and permits the locking member
44
′″ to readily radially expand as the cable
14
is further inserted in direction
60
. The cable
14
thus passes easily through the.bore of the locking member
44
″.
When the cable is pulled in the withdrawal direction
55
,
FIG. 16
, the locking member
44
′″ is pulled with the cable
14
due to its radially resilient gripping of the cable. The locking member and cable are pulled in the direction
55
to the position shown in
FIG. 16
wherein the locking member
44
′″ is secured wedged in place to the sleeve
94
and cable
14
. With the cable, sleeve and locking member so wedged, displacement of the cable
14
in the insertion direction
60
is possible at which time the locking member and the wedged sleeve
118
displace in unison to the left in the figure to the position shown to the left most end of the chamber portion
112
″. The shackle cable
14
can not be removed from the housing
110
.
In
FIGS. 19 and 20
a further embodiment of a sleeve is shown. Sleeve
136
is of uniform thickness sheet metal, e.g., steel, that is formed with a frusto-conical bore
138
and exterior surface
140
. The sleeve
136
is C-shaped and has a slit
142
for its full axial length. The small diameter end of the sleeve is rolled over at portion
144
to form a double thickness at this portion. The portion
144
supports the sleeve
136
in the mating housing bore which may be of complementary diametrical dimensions to closely receive the sleeve
136
. The bore
138
is uniformly tapered throughout its length. This sleeve is resilient radially and may also wedge in place in the housing chamber when forced into a narrowed chamber end (not shown) in the withdrawal direction
55
,
FIG. 15
, for example.
FIG. 21
illustrates a still further embodiment of a sleeve which may be used, in the alternative to the sleeves described above herein. In
FIG. 21
, sleeve
146
is sheet metal, e.g., steel, and is formed with a tapered bore and tapered external surface. It is similar to the sleeve
40
,
FIG. 5
, except that a slit
148
is formed in the sleeve similar to slit
142
,
FIG. 19
, in sleeve
136
. The slit
148
also causes the sleeve
146
to be radially resilient.
In
FIG. 22
, a further embodiment of a sleeve includes a sleeve
150
having a body
152
with a tapered bore and tapered external surface. The sleeve
150
is preferably made of sheet metal. An annular flange
154
is at the bore
156
larger diameter end. The sleeve
150
mates in a housing chamber (not shown) with complementary surface features.
In
FIG. 32
, the seal
10
of
FIG. 1
may exhibit several problems. First, the seal is relatively large and uses relatively a considerable amount of material, preferably zinc, which is costly. A second problem is in tightening the shackle
14
to the locked position shown. It is desirable to make the loop
170
as small as possible. In this example, the shackle
14
is stranded steel cable about {fraction (1/16)} to {fraction (3/16)} inch (1.6 mm to about 4.8 mm) in diameter. The center-to-center spacing d of the chambers
18
and
20
is about one inch (2.5 cm). The hole
30
has a relatively sharp comer
172
where the shackle
14
enters during insertion.
The spacing d limits the size of the loop
170
. The shackle
14
cable has to bend into the loop
170
in order for the end
58
to be pulled tightly through the housing chamber
20
. As the shackle end
58
is pulled or pushed through the chamber
20
and through the locking member
44
, the bend in the shackle engages the sharp comer
172
of the housing. This comer must be sharp because if chamfered or rounded, space will be provided between the shackle and the housing which will permit tampering tools to be forced into the chamber
20
in an attempt to unlock the locking member. This chamfering or rounding the comer
172
is therefore not acceptable.
Due to the bend in the shackle in the loop
170
, the portion
174
of the shackle at the entrance hole
30
tends to be inclined or bowed relative to the axis
28
of the chamber
20
. This inclination of the shackle causes the shackle portion
174
to dig into the corner
172
of the hole
30
making insertion of the cable difficult. The tighter and smaller the loop
170
, the greater this angle of insertion of the cable and the more difficult to insert the cable in direction
60
. Thus it has been determined that the one inch spacing d for the size cable being used as noted above is about the minimum possible spacing in order for the shackle to be inserted with a reasonable force. This minimum spacing thus requires excessive amount of material in the housing
16
. It is desirable to further reduce this spacing and the size of the housing without further increasing the insertion load on the shackle. This insertion load is due to dragging bent portion
174
over the comer
172
as the loop
170
is reduced in diameter. Should the spacing d be reduced in half to about {fraction (3/16)} inch (12.7 mm) to reduce the amount of housing material used, it becomes very difficult to insert and tighten the shackle
14
loop
170
to a desired diameter.
In
FIGS. 23-27
, seal
158
solves the above described problem. The seal
158
comprises a housing
160
having chambers
162
and
164
, locking member
166
and a sleeve
168
located in the housing chamber
166
. The locking member
166
is serpentine as described above in connection with the
FIG. 5
embodiment. The chamber
166
and sleeve
168
are also as described above in connection with the
FIG. 5
embodiment by way of example and may be identical to such elements.
The housing
160
in which chamber
162
is located has a body
178
. The body
178
has opposing end walls
180
and
182
, FIG.
26
. The wall
182
is preferably inclined about 45° to axis
182
of the chamber
164
, but may be at other angles. The housing
160
ends lie in and define two parallel planes
184
and
186
, FIG.
27
. The wall
182
,
FIGS. 26 and 27
, along the center axis
188
of the chamber
162
at plane
192
, where the chamber exits the wall
182
, is medially these two planes and lies in a plane that intersects the chamber
164
. The wall
182
is spaced distance x from the end
190
at plane
186
, FIG.
27
. Distance x is important as it has been discovered that this spacing permits a larger loop of the shackle for a given spacing d′ between the chamber
162
axis
188
and the chamber
164
axis
182
. This larger loop of the shackle thus reduces the drag and digging action in the corner
163
of the chamber
164
shackle insertion hole
194
, FIG.
26
.
In
FIG. 31
, seal
196
has a housing
198
having chambers
200
and
202
. The chambers are spaced apart a distance of about ½ inch for a cable of about {fraction (1/16)} to {fraction (3/16)} inch diameter instead of the on inch spacing of the embodiment of
FIG. 4
, all other parameters and elements being the same. Sleeve
204
is in chamber
202
and locking member
204
locks to the sleeve
204
. Shackle
208
end
208
′ is staked to housing
198
at stakes
210
. Shackle end
208
″ is locked to locking member
204
by locking member
206
. Shackle
208
portion p′ exits the housing
198
in the same plane
212
as the shackle end
208
″ portion p′ enters the housing
198
.
In comparison to the improved embodiment of
FIG. 30
, the loop L in
FIG. 31
is larger and this loop L is at about its smallest size. The portions p and p′ are inclined at the ingress to the housing
198
. The portion p′ inclination causes this portion to dig into the housing comer where it enters the housing chamber egress hole making further insertion of the cable difficult. It is so difficult to insert the cable to its final reduced loop L size that this size housing is impractical commercially. Therefore, it is impractical to reduce the housing
198
size to that of
FIG. 31
as compared to that of
FIG. 32
where the portions p and p′ enter and exit the housing in the same plane
212
.
In contrast, in
FIGS. 28-30
, the shackle
176
can be bent at a relatively larger angle ∀ at the housing
178
wall
182
as the shackle end
176
′ is pulled through the locking chamber
164
. In
FIG. 30
, the angle ∀′ permits a loop
214
to exhibit a smaller loop size y than otherwise possible for a housing reduced in dimension between the axes of the staking chamber and the locking chamber.
In the seal
158
of
FIGS. 25-27
, the shackle at its staked chamber egress and locking chamber ingress are not coplanar and the two locations are spaced from each other a distance x, FIG.
27
. This distance x is sufficiently great to permit significant reduction in housing size and material as well as reducing the insertion force of the shackle. For example, in the
FIG. 31
embodiment, the insertion force of the shackle may be about 10-12 lb. (4.6-5.6 kilogram) as compared to the
FIG. 30
embodiment, where the insertion force may be about half, e.g., 6 lb (2.8 kilogram) for a given set of materials and dimensions of the housing, cable, locking chamber, locking member and sleeve. There is a noticeable improved reduction in insertion load in the
FIG. 30
embodiment in the presence of a reduced spacing d′,
FIG. 26
, over that of the
FIG. 32
embodiment.
It will occur to one of ordinary skill in this art that various modifications may be made to the disclosed embodiments without departing from the spirit and scope of the invention. The disclosed embodiments are for illustration and not limitation. The invention is defined by the appended claims. For example, the axis of the staking chamber
162
,
FIG. 26
, need not be parallel to the locking chamber and may be inclined toward the top of the drawing sheet and to the right of the figure somewhat parallel to the shackle
176
,
FIGS. 29 and 30
, where the shackle exits the housing at wall
182
. This inclination may be at an angle determined for a given set of conditions in a given implementation.
Claims
- 1. A seal comprising:a housing made of a first material and having a tapered first chamber with opposing first and second ends, the housing having a first opening in communication with the ambient atmosphere and the chamber at least the chamber first end; a sleeve in the chamber having a tapered bore in communication with the opening and made of a second material different than the first material, the bore tapering in a first direction from a large transverse dimension adjacent to the chamber second end to a relatively smaller transverse dimension adjacent to the first chamber first end; a shackle having a free end for insertion into the sleeve tapered bore through the first opening in an insertion direction opposite the first direction; and a locking member being free to displace with the shackle in the first chamber and tapered bore and being arranged to wedge against and between the sleeve and shackle in the tapered sleeve bore when the shackle is displaced in the first direction, for receiving and for gripping the shackle.
- 2. The seal of claim 1 wherein the second material is stronger than the first material.
- 3. The seal of claim 1 wherein the second material is harder than the first material.
- 4. The seal of claim 1 wherein the sleeve is dimensioned to be fixed in place in the housing first chamber.
- 5. The seal of claim 1 wherein the sleeve is made of steel.
- 6. The seal of claim 5 wherein the sleeve has a length dimension and has a slit along the length dimension so that the sleeve is radially resilient.
- 7. The seal of claim 1 wherein the housing first chamber is tapered, the sleeve having an external surface that is complementary to the housing first chamber taper.
- 8. The seal of claim 1 wherein the locking member is serpentine.
- 9. The seal of claim 8 wherein the sleeve bore defines an axis, the locking member comprising a plurality of interconnected U-shaped loop members extending along the axis.
- 10. The seal of claim 1 wherein the housing is at least one of plastic and zinc, the locking member and the sleeve are steel.
- 11. The seal of claim 1 wherein the sleeve has a length between said chamber ends smaller than the chamber length between the chamber ends, the chamber having a transverse dimension relative to the sleeve outer dimension so that the sleeve can displace in the chamber with the locking member and shackle wedged to each other in response to displacement of the secured shackle in a direction opposite the first direction.
- 12. The seal of claim 11 wherein the sleeve has an outer peripheral surface, and wherein the sleeve tends to displace in the chamber in response to insertion of the shackle therein, further including means for securing the sleeve in the chamber in fixed position to restrain the displacement of the sleeve in response to said insertion.
- 13. The seal of claim 12 wherein the means for securing the sleeve includes staking means for staking the sleeve to the housing.
- 14. The seal of claim 1 having a second chamber for receiving the shackle portion locked to the housing including means for locking the shackle portion to the housing in the second chamber and having a third chamber between the first chamber and second chamber to minimize material in said housing.
- 15. The seal of claim 1 wherein the sleeve outer peripheral surface and the housing chamber have complementary tapers for receiving the sleeve in the first chamber, the sleeve having a tapered bore.
- 16. The seal of claim 1 wherein the sleeve, locking member and first chamber are dimensioned so that the sleeve axially displaces in the chamber in response to displacement of the shackle in a direction opposite the first direction and the sleeve and first chamber are dimensioned so that the sleeve catches in the first chamber to provide a resistance to displacement of the shackle in a direction opposite the first direction after the shackle is displaced in the first direction.
- 17. The seal of claim 1 wherein the sleeve has a tapered bore and complementary tapered external surface terminating at a radially outwardly extending flange at an end of the tapered external surface.
- 18. The seal of claim 1 wherein the sleeve is sheet material and has a tapered bore and complementary tapered external surface terminating at a smaller diameter end of the sleeve, the smaller diameter end including a folded over double thickness portion of sleeve material.
- 19. The sleeve of claim 18 wherein the sleeve has an axial extent and has a slit therethrough from the bore to the external surface for the axial extent.
- 20. The seal of claim 1 wherein the first chamber is circular cylindrical and the sleeve has a circular cylindrical external surface mating with the housing chamber and a tapered bore.
- 21. The seal of claim 1 wherein the first chamber has a first portion of circular cylindrical diameter, a second adjacent portion that tapers from the first portion to a larger diameter, and a third portion adjacent to the second portion of about the same diameter as the larger diameter and is circular cylindrical, the sleeve having a circular cylindrical outer surface and a tapered bore.
- 22. The seal of claim 1 wherein the shackle has a portion locked to the housing, said free end extending from the locked portion and from the housing in a first plane, said housing opening terminating in a second plane different than the first plane so that the shackle engages the housing opening during said insertion in the second plane.
- 23. The seal of claim 22 wherein the first plane intersects the housing first chamber and is normal to the insertion direction.
- 24. The seal of claim 22 wherein the housing has a second chamber, said shackle portion being locked to the housing in the second chamber, said second chamber having an exit plane through which the shackle passes at an exterior surface of the housing, the exit plane intersecting the housing first chamber.
- 25. The seal of claim 22 wherein the housing has third and fourth ends and a second chamber, said shackle portion being locked to the housing in the second chamber, the second chamber terminating at a housing fifth end medially the first and second ends.
- 26. The seal of claim 25 wherein the fifth end is inclined relative to the insertion direction.
- 27. The seal of claim 1 wherein the housing has a second opening in communication with the ambient atmosphere and with the first chamber at the chamber second end; said sleeve mating with first chamber with a complementary configuration, the sleeve tapered bore in communication with the second opening and comprising harder material than the first material, the locking member for radially resiliently gripping the shackle passing through the locking member bore.
- 28. A seal comprising:a housing having first and second ends lying in spaced parallel planes, the housing having a first chamber terminating at the second end at a first opening in communication with the ambient atmosphere and a second chamber terminating at a third housing end at a second opening in communication with the ambient atmosphere, the second opening being medial the spaced parallel planes; a shackle having a first end secured to the housing in the second chamber and having a free end exiting the second chamber through the second opening, the free end for insertion into the housing first chamber through the first opening in an insertion direction; and a locking member with a bore located in the first chamber, the locking member for receiving and for gripping the shackle passing through the locking member bore, the locking member and chamber being arranged to wedge the locking member in the chamber when the shackle is displaced in a withdrawal direction opposite the insertion direction.
- 29. The seal of claim 28 including a sleeve captured in the first chamber, the locking member and sleeve being arranged to wedge the locking member against the sleeve in response to displacement of the shackle in the withdrawal direction.
- 30. The seal of claim 28 wherein the sleeve comprises material that is harder than the housing.
- 31. The seal of claim 28 wherein the third housing end is inclined relative to the insertion direction.
- 32. The seal of claim 31 wherein the third housing end is inclined in the range of about 30° to 75°.
- 33. The seal of claim 28 wherein the third housing end has a surface that defines a plane that intersects the first chamber.
US Referenced Citations (15)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1432642 |
Apr 1976 |
GB |