LOCKING DEVICE AND METHOD FOR CATCH BASIN AND MANHOLE COVERS, AND THE LIKE

DISPOSITIF ET PROCEDE DE VERROUILLAGE POUR COUVERCLES DE PUISARD ET D'EGOUT, ET INSTALLATIONS SIMILAIRES

English Abstract

A locking device and method for securing a cover as for a catch basin or
manhole in position including two elongate members pivotally connected
together end to end so as to be able to articulate. The members are held
aligned while being inserted through a cover opening suspended in Said opening
an a flange an the upper member, the lower member then released to be angled
by a spring force to wedge against sidewall and an edge of the cover opening.
A holt extending through the top threaded into a trunnion extending across an
intermediate space of the lower member draws the lower member up to create a
powerful wedging action to prevent cover removal. The holt head is recessed
into the flange and configured with a special shape engageable only with a
special tool to be tamper resistant. A protective plastic cap covers the bolt
head and has protrusions sheared off when the cap is removed to provide a
tamper indication. A miniature radio transmitter can be installed beneath the
cap to transmit an alarm signal when the cap is removed. The locking device is
used with a modified manhole cover by installing an adaptor sleeve defining a
rectangular opening through which the locking device is inserted, and by
connecting an extension arm to the lower member bottom end by use of a shear
pin and pivot holt allowing release of the locking device and cover in the
event of an explosion.

French Abstract

L'invention concerne un dispositif et un procédé de verrouillage permettant de fixer un couvercle destiné à un puisard et un égout à une position qui comprend deux éléments allongés reliés ensemble au niveau de leurs extrémités de manière pivotante pour pouvoir s'articuler. Ces éléments sont maintenus alignés, tandis qu'ils sont introduits à travers une ouverture du couvercle suspendue dans l'ouverture sur un rehaut situé sur l'élément supérieur, l'élément inférieur est alors libéré pour être incliné par le biais d'une force d'un ressort, de façon à se coincer contre la paroi d'un mur et un rebord de l'ouverture du couvercle. Un boulon s'étendant à travers la partie supérieure filetée en un tourillon qui s'étend à travers un espace intermédiaire de l'élément inférieur tire cet élément vers le haut pour créer une action de clavetage puissante, de façon à empêcher le retrait du couvercle. La tête du boulon est logée dans le rehaut et elle est conçue avec une forme spéciale dans laquelle seul un outil spécial peut s'imbriquer de manière à garantir l'aspect inviolable. Une coiffe en plastique de protection recouvre la tête du boulon et présente des protubérances cisaillées, lorsque la coiffe est retirée pour fournir une indication de détérioration. Un émetteur radio miniature peut être installé en-dessous de la coiffe de manière à transmettre un signal d'alarme, lorsque la coiffe est retirée. Ce dispositif de verrouillage est utilisé avec un couvercle d'égout modifié par installation d'un manchon d'adaptateur formant une ouverture rectangulaire à travers laquelle le dispositif de verrouillage est introduit, et par attachement d'un bras d'extension à l'extrémité inférieure de l'élément inférieur au moyen d'une goupille de cisaillement et d'un boulon à oeil, ce qui permet la libération du dispositif de verrouillage et du couvercle en cas d'explosion.

Claims

WHAT IS CLAIMED IS:
1. A locking device for a cover structure overlying an opening defined in part
by a
sidewall, said cover structure recessed within a perimeter frame extending
around said opening
and having a through opening adjacent a side thereof, said device comprising:
an upper elongated member having a flange at a top end configured to suspend
said
upper member on said cover extending into said through opening;
a recess extending into said flange and terminated by a bottom wall;
a hole extending into said bottom wall and through a lower end of said upper
member;
a threaded bolt slidably received into said hole and protruding out said lower
end of said
upper member, said bolt having a head received into said recess;
a lower elongate member having spaced walls defining a space having said lower
end of
said upper member fit therein, said threaded bolt threadably received into a
threaded hole in a
trunnion rotatably supported in said lower member and extending across said
space;
at least one spring connected at one end to said upper member and at another
end to said
lower member, said at least one spring located to urge said members together
in an end to end
direction and also to urge relative rotation of said members about said
trunnion;
a detent mechanism comprising a first detent feature on the lower end of said
upper
member and a second detent feature on said lower member engaging said first
detent feature
with said members in end to end abutment so as to prevent relative rotation
about said trunnion;
said bolt able to push said lower member away from said upper member against
said
spring force to cause disengagement of said detent features allowing said
members to articulate
by relative rotation about said trunnion; and
wherein said lower member is configured to be rotatable relative to said upper
member
to enable engagement between said lower member and said sidewall and between
said lower
member and an edge of said cover structure.

2. The locking device according to claim 1 wherein said lower member is formed
with at
least one notched contour on an upper end rotated to engage said edge of said
cover structure
upon disengagement of said detent features and rotation of said lower member
by said at least
one spring.
3. The locking device according to claim 2 wherein a bottom end of said lower
member is
formed with teeth engaging said sidewall upon articulation of said upper and
lower members to
establish a wedging action between said lower member, said sidewall, and said
cover structure.
4. The locking device according to claim 3 wherein advance of said bolt in
said threaded
hole of said trunnion causes raising of said lower member to increase said
wedging action by the
reaction of said head on said bolt engaging said bottom wall of said recess in
said upper member
to increase the pressure of said teeth on said lower end of said lower member
against said
sidewall and said notched contour against said cover structure.
5. The locking device according to claim 1 wherein said bolt head is formed
with an
irregular contour engageable only with a special tool to be tamper resistant
after said bolt is
tightened.
6. The locking device according to claim 5 wherein said bolt head is
substantially enclosed
in said recess after said bolt is tightened.
7. The locking device according to claim 6 further including a molded plastic
cap received
over said bolt head in said recess.
11

8. The locking device according to claim 7 wherein said cap has at least one
protrusion
contoured in a pocket in said recess upon being installed, said at least one
protrusion deformed
upon removal of said cap to provide a tamper indicator.
9. The locking device according to claim 1 wherein said lower member has a
pair of
spaced apart parallel walls defining said space receiving said upper member,
said sides
connected at a bottom end of said lower member, said trunnion received in
aligned bores in said
sides.
10. The locking device according to claim 9 wherein each wall of said lower
member is
formed with a bore aligned with the bore in the other wall, said trunnion
slidably received in
said bores.
11. The locking device according to claim 10 wherein said trunnion is located
at an
intermediate location along the length of said lower member.
12. The locking device according to claim 1 wherein the at least one spring
includes two
springs, and the two springs are each connected at either end to said upper
and lower members
respectively, said springs connected at one end to one side of one member and
at the other ends
to an opposite side of the other member to create said rotational force
resisted by said detent
mechanism.
12

13. The locking device according to claim 12 wherein the two springs are
located so as to
urge said members together in an end to end direction and also so as to urge
relative rotation of
said members about said trunnion, and wherein both of said springs are
partially wrapped
around said trunnion in extending from said upper member to said lower member.
14. The locking device according to claim 1 wherein said detent features
comprise a flat tab
projecting from one member and wherein the recess is formed in the other
member and
configured for receiving the tab therein, said flat tab overlying said recess
with said members in
said end to end aligned position.
15. The locking device according to claim 7 further including a radio
transmitter located
beneath said cap and activating a transmitted signal upon removal of said cap.
16. The locking device according to claim 1 wherein said cover is a manhole
cover and
further including an adaptor sleeve fixed in said manhole cover having said
cover opening
formed thereon.
17. The locking device according to claim 16 further including an extension
arm fixed to
the lower end of said lower member to be engageable with a manhole sidewall.
18. The locking device according to claim 17 wherein said extension arm is
connected to
said lower member by a shear pin which will be severed by a predetermined
force to allow
release of said locking device in the event of an explosion.
13

19. A method of securing a cover structure in position over a space below said
cover
defined in part by a sidewall, said cover structure recessed within a frame
and having a through
opening adjacent said sidewall, comprising the steps of:
pivotally connecting an upper and a lower elongated members together end to
end so as
to able to be articulated;
providing at least one spring coupled to said upper and lower members in
locations
configured for producing a force tending to cause said members to articulate
by angling said
lower member with respect to said upper member about said pivotal connection,
said at least
one spring member being configured for angling said lower member so as to
enable engagement
between said lower member and said sidewall and between said lower member and
an edge of
said cover structure;
forming detent features on said upper and lower members, said detent features
being
engageable to hold said members in an aligned condition, said detent features
being
disengageable to allow articulation of said members;
providing a detent release mechanism configured for disengaging the detent
mechanism
to allow articulation of said members after insertion of said members into
said cover opening;
suspending said connected members on said cover structure extending through
said
cover opening;
actuating said detent release mechanism to disengage said detent mechanism,
thereby
releasing said members to allow articulation thereof; and
engaging said sidewall with said lower member and simultaneously engaging said
lower
member with an edge of said cover structure so as to wedge lower member
therebetween to
secure said cover in place.
14

20. The method according to claim 19 further including the step of drawing
said lower
member up towards said upper member after engagement of said lower member with
said
sidewall and cover structure to increase a wedging force of said lower member
between said
sidewall and said cover structure, to join said cover against said frame.
21. The method according to claim 20 wherein said step of pivotally connecting
said upper
and lower members together comprises the step of installing a rotatable
trunnion in said lower
member and threadably engaging said trunnion with a threaded bolt extending
through a hole in
a wall in said upper member and a threaded cross hole in said trunnion, said
bolt having a head
seatable on said bottom wall.
22. The method according to claim 21 wherein said step of drawing said lower
member
towards said upper member comprises the step of rotating said bolt in said
threaded hole in said
trunnion with said bolt head abutting said bottom wall.
23. The method according to claim 19 wherein said step of suspending said
members
includes the step of forming a flange on said upper member configured to rest
on surfaces
adjacent said cover opening.
24. The method according to claim 21 further including the step of forming
engagement
surfaces on said bolt engageable only with a special tool and advancing said
bolt with said
special tool to be tamper resistant.

25. The method according to claim 24 further including the step of recessing
said bolt head
within a flange formed on said upper member.
26. The method according to claim 25 further including the step of installing
a tamper
indicator plastic cap over said bolt head.
27. The method according to claim 26 further including forming a contour on
said lower
member to securely be captured by said cover structure.
28. The method according to claim 19 wherein said cover structure comprises a
cover and
an adaptor sleeve mounted to said cover, the adapter sleeve having a portion
formed with a
rectangular opening configured for receiving said connected members therein.
29. The method according to claim 28 further including the step of attaching
an extension
arm engageable with a sidewall of said manhole to said lower member bottom end
by a shear
pin able to release said locking device in the event of an explosion.
30. The method according to claim 19 further including the step of installing
a plurality of
said locking devices on opposite sides of said cover.
31. The method according to claim 30 further including the step of installing
a bolt on the
underside of said manhole cover adjacent a manhole cover flange to prevent
lifting of both sides
of said manhole cover.
16

32. A system for locking down an enclosure comprising:
a cover for said enclosure;
a locking device received in a cover opening, the locking device including:
a first member;
a second member rotatably coupled to the first member;
at least one spring member coupling the first member with the second member so
as to
urge rotation of the second member with respect to the first member due to
forces exerted by the
at least one spring member;
a bolt coupling the first member to the second member such that the second
member is
engaged with the first member so as to prevent rotation of the second member
due to forces
exerted by the at least one spring member when the bolt is in a first
position, and such that
rotation of the bolt to place the bolt in a second position different from the
first position
disengages the second member from the first member so as to enable rotation of
the second
member due to forces exerted by the at least one spring member;
said bolt having a special head shape;
a socket tool adapted to mate with said special shaped bolt head; and
a seal covering said bolt head and having a tamper indicator when removed.
33. The locking device of claim 1 wherein the cover structure comprises a
cover and an
adapter sleeve fixed in a hole formed in the cover, and wherein the lower
member is configured
to be rotatable relative to said upper member to enable engagement between
said lower member
and an edge of said adapter sleeve.
17

Description

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1 LOCKING DEVICE AND METHOD FOR CATCH BASIN AND
2 MANHOLE COVERS, AND THE LIKE
3
4
Background of the Invention
6 This invention concerns locking devices and methods, more particularly such
7 devices and methods as applied to covers used for catch basins and manholes
installed in
8 roadways for access to utilities, i.e., water, gas, communications,
electricity. These covers are
9 provided in order to keep out debris but also to present a supporting
surface for pedestrians
and vehicles on the surrounding roadway surface. If the covers are removed,
the opening to a
11 catch basin or manhole presents a severe hazard to vehicles and pedestrian
traffic. Removal
12 of these covers by vandals or scavengers has become an increasing problem
which has
13 created an urgent need for some means for securing the covers in place.
There are no locking
14 devices incorporated in existing catch basin and manhole covers such that
providing a simple
retrofit for existing covers is highly desirable. Such devices must be rugged
to withstand
16 traffic and weather and the efforts of vandals or terrorists to remove
them. The large numbers
17 involved dictate a simple installation method to minimize labor costs. The
device must not
18 present an obstruction in the roadway, particularly for snow plows, nor a
tripping hazard to
19 pedestrians.
It is the object of the present invention to provide a locking device and
method
21 which can quickly be installed to provide a simple retrofit to existing
manhole and catch
22 basin covers.
23 It is a further object to provide such a device which is rugged and able to
24 withstand abuse and heavy traffic and reliably secure such covers in place
without creating an
obstruction in the roadway.
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1 Summary of the Invention
2 These objects and others which will be appreciated upon a reading of the
3 following specification and claims are achieved by providing a locking
device insertable into
4 an opening in the cover adjacent a sidewall of the cover frame. The device
is comprised of an
upper and a lower member which are connected to each other end-to-end so as to
allow
6 articulation of the lower member to install the device, the members are
initially set in an end-
7 to-end alignment and are inserted into the cover opening. The members are
held in end to
8 end alignment, with a detent mechanism including interfit detent features
and the respective
9 members held in that position by one or more springs so as to connected
exert a force pulling
the members together to maintain the interfit detent features in engagement.
11 A bolt having a tamper resistant head extends through a hole in the upper
12 member and is left hand threadably received in a trunnion member rotatably
mounted to the
13 lower member extending across a space defined by space sidewalls included
in the lower
14 member. The bolt can be pushed down against a bottom wall of the upper
member to counter
the spring force and thereby allowing disengagement of the interfit detent
features. The
16 spring or springs then cause the lower member to be pivoted on the trunnion
with respect to
17 the upper member and thereby angled towards the sidewall adjacent the
opening until the
18 bottom end of the lower member engages the same. Teeth are preferably
formed along the
19 bottom end edge of the lower member engaged with the sidewall.
Notch contours on the upper end of the lower member at the same time are
21 moved to engage an edge of the cover opening through which the device is
inserted.
22 The bolt is then driven on its threaded connection to the trunnion by a
special
23 tool socket to draw the lower member up, the upper member having a flange
overlying the
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1 cover to provide a reaction surface. This creates a powerful wedging of the
lower member
2 between the sidewall and opening edge, preventing lifting of that side of
the cover. By
3 installing four locking devices, two on each side of the cover, the cover is
wedged securely in
4 its opening to prevent its removal.
The bolt head is received within a recess in the top of the upper member and
6 has driving contour requiring a special tool to prevent removal of the
locking device by the
7 use of standard tools.
8 A plastic cap is placed over the bolt head and in the recess to prevent
9 weathering of the bolt threads and the entrance of plugging dirt and debris.
Special features
on the cap provide a tamper indication if the cap is removed.
11 A special version of the device is used for manhole covers, in which an
12 adapter sleeve is fitted into a round hole bored into the manhole cover and
secured to the
13 cover with bolts received in threaded holes formed into the underside of
the manhole cover.
14 The upper member is received in a central rectangular opening in the
adapter sleeve, the
upper member having a round flange smoothly overlying the adapter sleeve top
surface
16 adjacent the rectangular opening.
17 An extension arm is secured to the bottom end of the lower member to enable
18 the toothed bottom edge of the extension arm to reach a sidewall edge
located further from
19 the manhole cover opening in which the locking device is inserted. The
extension arm is
attached using a pivot bolt and a shear pin so that the cover can be released
and blown free in
21 the event of a gas explosion to prevent structural damage. The adapter
sleeve presents an
22 opening wall which projects downwardly to present an edge engageable with
the lower
23 member notched contours to establish a wedging lock as in the catch basin
version of the
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1 locking device.
2 A special radio signaling device can also be built into the cap, able to
provide
3 a remote alarm via a repeater amplification to a central station if
tampering is detected, which
4 can also be used to locate a catch basin or manhole when a cover has been
removed or
tampered with.
6
7 Description of the Drawings
8 Figure 1 is an exploded perspective view of a locking device according to
the
9 present invention.
Figure 2 is a front view of a locking device according to the present
invention.
11 Figure 3 is a rear view of the locking device shown in Figures 1 and 2.
12 Figure 4 is a side view of the locking device shown in Figures 1-3 inserted
in a
13 catch basin cover, shown with the adjacent sidewalls in fragmentary form.
14 Figure 5 is a side view of the inserted locking device of Figure 4 in the
articulated condition of the upper and lower members.
16 Figure 6 is a top view of the upper member showing the tamper resistant
bolt
17 shape.
18 Figure 7 is a side view of the upper member in phantom lines, showing the
19 tamper resistant bolt seated with a cap in place on the bolt head covering
the upper member
recess.
21 Figure 8 is a perspective view of the plastic flanged cap shown installed
in
22 Figure 7.
23 Figure 9 is a top view of a catch basin cover with four locking devices
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1 according to the invention installed therein.
2 Figure 10 is a diagrammatic view of an installed cap with a radio
transmitter
3 monitor.
4 Figure 11 is a side view of an installed modified locking device having a
configuration suited to the manhole covers shown, with adjacent fragmentary
portions of the
6 manhole cover frame sidewall shown in section.
7 Figure 12 is a plan view of a manhole cover with the locking device
installed.
8 Figure 13 is a front view of the lower member of the manhole cover locking
9 device shown in Figure 11, with a fragmentary portion of the extension arm
installed thereon.
Figure 14 is a sectional view of fragmentary portion of the manhole cover and
11 adapter sleeve showing one of the attachment ears and bolts.
12
13 Detailed Description
14 In the following detailed description, certain specific terminology will be
employed for the sake of clarity and a particular embodiment described in
accordance with
16 the requirements of 35 USC 112, but it is to be understood that the same is
not intended to be
17 limiting and should not be so construed inasmuch as the invention is
capable of taking many
18 forms and variations within the scope of the appended claims.
19 Referring to the drawings, the locking device 10 according to the present
invention is designed to be installed by being first inserted into an opening
12 in a catch basin
21 cover 14 overlying an opening defined by a sidewall 16.
22 The locking device 10 includes a generally rectangular upper and lower
23 moderately elongated members 18, 20, which are preferably constructed of
high strength steel
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1 and connected together end-to-end in a manner allowing articulation
therebetween. Prior to
2 installation, the members 18, 20 are set in an end-to-end aligned position
as shown in Figures
3 2 and 4. The upper member 18 has a flange 22 at the top which overlies the
cover structure
4 adjacent the opening 12 to suspend the locking device hanging through the
opening 12 and
into the space below the cover 14. The edges of the flange 22 are is rounded
to present a
6 smooth contour.
7 The upper member 18 is generally rectangular and is sized to be received
8 between a pair of spaced upstanding walls 24 included in the lower member
20. The upper
9 member 18 has a depending rectangular tab 26 on one side of a radiused
bottom wall 28
which is interfit to a rectangular recess 30 in a cross web 32 at the rear of
the bottom member
11 20 extending between the walls 24. The tab 26 and recess 30 comprise detent
features of a
12 detent mechanism for releasably holding the upper and lower members 18, 20
in their initially
13 set aligned position by preventing rotation of the lower member 20 about a
trunnion 40. The
14 detent mechanism also includes one or more coil springs 34 which are each
connected at
either end to the upper and lower members 18, 20.
16 For this purpose, slotted ears 36 are formed on the bottom of one side of
the
17 upper member 18 and slotted ears 38 are formed on the inside of the spaced
walls 24 on the
18 opposite side of bottom member 20. The springs 34 thus extend down and
around trunnion
19 40 and over to the lower tabs 38, exerting an end to end pulling force on
the members 18, 20
tending to maintain engagement of the tab 26 and recess 30.
21 The springs 34, since they are wrapped around the trunnions 40 also urge
22 relative rotation of the upper and lower members 18, 20, but this is
resisted by the interfitting
23 engagement between the tabs 26 and recess 30 preventing rotation of the
upper and lower
6

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I members 18, 20 about the trunnion 40.
2 The upper member 18 has a recess in its upper end comprised of cylindrical
3 bore 42 extending into the top thereof down to a bottom wall 44. An aligned
smaller
4 diameter through hole 46 extends through the bottom wall 44 and slidably
receives a bolt 48
therein. Bolt 48 has a tamper resistant shaped head 50 (seen in Figure 6) and
a left hand
6 threaded body 52 which is threadably engaged with a through cross bore 54
extending
7 through the trunnion 40. Trunnion 40 is rotatable in aligned bores 56 in the
spaced walls 24.
8 The bolt 48 is initially installed so as to not engage the bottom wall 44.
9 After insertion of the locking device 10 in the opening 12, the bolt head 50
is
pushed down against the bottom wall 44 to push the lower member 20 down and
away from
11 the upper member 18 against the resistance of the springs 34.
12 This repositions the recess 30 down to disengage the tab 26, which allows
the
13 springs 34 to rotate the lower member 20 about trunnion 40 as shown in
Figure 5 until the
14 toothed bottom end 58 engages the catch basin sidewall 16.
At the same time, a notch contour 60 in the top of each spaced wall 24 are
16 both angled towards the bottom edge 62 of the opening 12 in the cover 14 to
engage the same
17 (Figures 4 and 5).
18 The bolt 48 is then rotated by use of a special socket tool (not shown)
19 contoured to engage the angled unequal flats 64 on the bolt head 50 (Figure
7). The size of
the bore 42 allows the tool to engage the bolt head 50 but leaves insufficient
clearance to be
21 engaged by adjustable tools to be tamper resistant.
22 Advance of the bolt 48 causes its left hand thread engagement to lift the
now
23 articulated lower member 18 to securely wedge the same tightly between the
sidewall 16 and
7

CA 02495662 2010-11-04
I edge 62. When four devices 10 are installed, two on each side of the catch
basin cover, this
2 will preventing removal of the cover 14.
3 A plastic cap 66 (Figures 7, 8) is provided to be fit over the bolt head 50
to
4 prevent debris to enter the space around the bolt head 50.
The cap 66 has protrusions 68 on portions 69 defined by slots 67 snap fit into
6 drain openings (not shown) provided in the bottom of the bore 42 the upper
member 18. The
7 bore 42 is formed with shallow grooves 65 to aid in aligning the protrusions
68 and a shallow
8 counterbore 61 to accommodate a cap flange 63. The protrusions 68 are broken
off when the
9 cap 66 is removed by use of a pronged tool engaging pockets 72 in the cap to
give evidence of
tampering.
11 Figure 10 shows a miniature radio transmitter-battery unit 78 installed
beneath
12 the cap 66, which can transmit a signal via a repeater amplifier system
to.a remote location.
13 Upon removal of the cap 66, the radio signal is interrupted so that an
intrusion alarm can be
14 triggered at the remote location. This signal can also be varied to locate
a catch basin without
a cover.
16 The device 10 can be adapted for use with a modified manhole cover 80, as
17 shown in Figure 11, in which a hole 82 bored into the under side of the
manhole cover 80 to
18 be able to receive an adapter sleeve 84 fixed in the hole 82 by ears 85 and
bolts 87 threaded
19 into holes 89 machined into the underside of the cover 80 (Figure 14). A
rectangular opening
86 is formed in the adapter sleeve 84, extending completely through the sleeve
84. An edge
21 88 is created on a lower side of the sleeve 84 positioned to be engaged by
the notch contours
22 60 as described above. The lower end of the adapter sleeve 84 is cut off at
an angle as shown
23 in Figure 11 to provide clearance for proper articulation of the lower
member 20.
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1 The lower member 20 has an extension arm 90 secured thereto with a pivot
2 bolt 91 an a shear pin 92 and has a toothed end engageable with manhole
sidewall 94. If an
3 explosion occurs, the shear pin 92 is severed, the extension arm 90 swings
free about the axis
4 of the pivot bolt 91 and the cover 80 is allowed to blow free.
A second bolt 96 is installed on the underside of the manhole cover 80,
closely
6 to the opposite side of the manhole cover flange 100. Optionally, a second
sleeve and lock
7 assembly can be installed in lieu of bolt 96 180 apart from each other.
8
9