CN2823334Y - Anti-theft shifting-proof manhole cover device - Google Patents

Abstract

The utility model discloses an anti-theft shifting-proof manhole cover device, which comprises a manhole cover, wherein the manhole cover is provided with more than one concave-convex groove block, and the concave-convex groove block is provided with a holding surface for a lifting tool on-off. The holding surface of the concave-convex groove block is one of the vertical surface and the inclined surface, and the holding surface can have a slip-proof structure. The shape of the concave-convex groove block can be any one of the shapes, such as rotundity, rectangles, triangles, polygons or circularity. The concave-convex groove block can be a downward blind hole, and the blind hole is perfused with sealant, gypsum or other fillers. The concave-convex groove block can also be an upward convex groove block, and a slot formed in each convex groove block is perfused and filled with reinforced concrete as fillers. The manhole cover of the utility model can not be found any pick-up point of opening the manhole cover when the robber steals the manhole cover, and the manhole cover has the antitheft effect while in use to ensure the pavement safety and avoid the dangers.

Description

The anti-theft and turnover preventing manhole cover device

Technical field

The utility model relates to a kind of anti-theft and turnover preventing manhole cover device.

Background technology

Press, in modern construction project, various pipelines and Facilities Construction all give undergroundization, in order to protection road safety of person vehicle and reduce the life that it disturbs people, and increase the look of the city aesthetic feeling.But the use of any subterranean pipe line and facility has the demand of maintenance or enlarging installing unavoidably, so must in position bury well lid and cage underground, and with the carrying out of convenient aforementioned work.Yet, because the texture material of well lid and cage is good, durable in use, dark rich economic worth, but because of monitoring constantly, so become one of favorite prey of stealer.

All be provided with hole or related facility that the breakdown well lid is used on the present well lid, the breakdown origin of force is arranged when making things convenient for the breakdown well lid, cause existing well lid and cage to there is no suitable theft preventing method, be at most the weight that can only increase well lid and cage itself, and well lid and manhole cover base often are embedded on the road basis, as well lid suddenly by the deathwatch, traffic bound is crossed well lid, and well lid meeting escape causes car crash.According to media report, existing well lid true case stolen, that make the people fall into the interior death of wellhole takes place, except punishing severely the personnel of committing a crime, the most basic road is still the anti-theft technique of strengthening well lid and manhole cover base, make stealer when the breakdown well lid, have no the origin of force of breakdown well lid, and make it lose the wish of stealing well lid, stealer can't be finished steal action.

Existing well lid is arranged on the carriageway more, because the vehicle dealing is frequent, causes well lid to jump out of the well head of manhole cover base, has a strong impact on road safety.The back finds that its principal element is as follows after deliberation:

One, well lid both had been arranged on the carriageway, through the wheel spreading, with the passing of time wear and tear and aging cracking, and after more renewing well lid, be that same group model is made moulding because of newly well lid and old manhole cover base are non-, cause the horizontal clearance of well lid and manhole cover base bigger, vertically be uneven.

Two, the manufacturing of well lid finished product all uses sand mo(u)ld perfusion to form, and because of the granular size of sand can't be consistent, causes well lid and the manhole cover base exposure level face can't be smooth, and the vertical plane space is too big.

Three, in the sand mo(u)ld filling process, form removal is dealt with improperly, makes the well lid distortion through process of expansion and contraction.

Four, according to checking and accepting regulation, the only sampling inspection of well lid finished product, so that be difficult to all check and accept its whether compliant size.

Five, construction or attendant open after the well lid, and finger stone, the silt particle that will not fall to stay when restoring on the manhole cover base apical margin be removed clean.

Six, well lid places on the carriageway, is positioned at the route of the normal process of wheel just as its position, and on-the-spot roadway often can be found two wheel traces, normal for a long time after, well lid is under the wheel vestige, well lid and manhole cover base are worn.Through construction or after the attendant opens well lid, be difficult to put back to the origin-location when restoring, cause the bonding surface injustice between well lid and manhole cover base, and make garage its when going up generation beat or escape.

Relevant above-mentioned deletion analysis, there is too many case to follow in fact, wherein as the traffic accident together that January 23, emerging bridge took place in the Taibei city, Taiwan Province, P.R.china in 1989, this cycling start seed of trouble is according to police investigation, to be a vehicle spreading be covered in the unexpected escape of cable culvert pipe well lid on the bridge floor in telecommunication bureau to its accident reason, cause follow its afterwards a passenger traffic bus of process bang into the well head of manhole cover base, and being upspring, flies away from whole vehicle body, and be pressed onto on the car of head-on sailing, cause four passenger's car crashes then and there on the car.Same case, the BeiJing, China caused three cyclists car crash accident then and there to take place in 2004.

According to above-mentioned traffic accident incident, behind utility model people field research, learn that it causes trouble process as shown in Figures 1 to 4, describe in detail now as the back:

Highway bridge design specifications regulation according to U.S.'s continent highway and transportation official association (AASHTO) traffic technique standard: the wheelbase Dd of standard open freight car is 4.25m, if road speed is 60km/hr, well lid RF is 0.676m, then works as the time starting point to be: ∑ T dR 〉=0

dR≥O

Front-wheel through well lid rear end R to time of front end F is:

T RF＝ RF/v＝0.676m/(60×1000m/hr)×60×60＝0.04056sec

Trailing wheel to the well lid rear end R time is:

T DR＝( Dd- RF)/M＝(4.25m-0.676m)/(60×1000m/hr)×60×60＝0.21444sec

Via above-mentioned formula, as shown in Figure 1, before vehicle no show well lid, well lid is as excellent as before, but well lid and manhole cover base exposure level face excesssive gap, vertical plane partly is uneven.Continue as shown in Figure 2, during the well lid of vehicle front-wheel contact then rear end R point, its time T dR is a starting point, because of exposure level face excesssive gap, is uneven between well lid and manhole cover base again, causes the perk of well lid front end F point, and it highly is H1.Continue as shown in Figure 3, then the vehicle front-wheel because of well lid front end F has apart from H1 with cage, adds moment first time collision effect when T RF=0.0405sec arrives well lid front end F, make the R perk of well lid rear end, highly to be H2 be high (H2＞H1) than front end for it.When the vehicle front-wheel just will leave the well lid front end, when being added in the front end of well lid because of vehicle gravity, the existing H1 distance that falls, add this for the second time moment collision effect, cause the well lid rear end to have upwards higher to fall apart from H2, promptly the vehicle front-wheel leaves the well lid front end, and well lid promptly becomes the seesaw action.Continue as shown in Figure 4, when T DR=0.214sec, when vehicle rear wheel collides well lid rear end R, well lid is hit from original position at last, cause the car crash major traffic accidents, jeopardize public popular safety.

Other consults Fig. 5 to shown in Figure 9, because vehicle imposes on the drag force or the compressive force effect of well lid, makes well lid produce anti-clockwise power and jumps out of the well lid pedestal, also can cause the harm of traffic accident, its process as described later:

At first, as shown in Figure 5, owing to have the space between well lid and manhole cover base, when the loaded vehicle front-wheel was pressed onto an end of well lid, the other end can perk.Continue as shown in Figure 6, then front-wheel continues to advance and since wheel impose on well lid execute drag force and compressive force, make well lid produce the power of counter rotation, the peak that takeoff this moment is also rotated by counter-clockwise direction.Continue as shown in Figure 7, current wheel load cross the well lid distal edge along the time, the peak that takeoffs moves to the right back, at this moment, perk end height has promptly exceeded road ground.Continue as shown in Figure 8, front-wheel through after, well lid be subjected to effect of inertia still can continue the rotation raise up.Continue as shown in Figure 9, according to trailing wheel to the well lid rear end R time be T DR=0.214sec, the obvious vehicle rear wheel of in this very brief time, being passed through, the back acies of will inevitably overtaking collision kicking up to well lid, because the enormous impact power of loaded vehicle, well lid after being impacted is flown out to right front rotation, influence road safety.This shows that above-mentioned known well lid still has many disappearances with being used in combination of manhole cover base, real non-one kindhearted design, and demand urgently being improved.

Again, in known relevant well lid and manhole cover base technology, have quite a lotly, be its typical case as No. the 481704th, TaiWan, China patent announcement, bulletin No. 427374 and several M240035 number of certificate number, M244316 number etc. and represent case in order to case before the patent that prevents the stolen and design of well lid or manhole cover base; Case before the patents that design in order to prevent well lid escape manhole cover base quite a lot is also arranged in addition, as No. the 211835th, TaiWan, China patent announcement, No. the 160395th, bulletin, No. the 195309th, bulletin and announce No. 491310, Chinese patent 20042006158.1 etc. and be its typical case and represent case.So, the well lid of these known cases and manhole cover base or disappearance on the structure design is arranged, and significant disadvantages is that these known cases can't reach the anti-escape of well lid and manhole cover base and antitheft dual-use function simultaneously, and the necessity that is improved is in the lump really arranged.

Summary of the invention

The purpose of this utility model provides a kind of anti-theft and turnover preventing manhole cover device, it can make stealer when stealing well lid, on the well lid surface, can't utilize general common tool insertion or hook to hold hole as usual, and then more can not find the origin of force of any breakdown well lid, so that well lid has never by deathwatch's function, and then guarantee road surface safety and avoid causing danger.

Another purpose of the present utility model is to provide a kind of anti-theft and turnover preventing manhole cover device, it utilizes well lid edge to have extended element downward more than, the corresponding location of fill-in well cage retaining is waled, make well lid and manhole cover base constitute appropriate gap, constituting an overall structure body, is that well lid extremely can't escape.

Another purpose of the present utility model is to provide a kind of anti-theft and turnover preventing manhole cover device, and it has antitheft, anti-escape function, has solved displacement simultaneously, falls, noise, slippage, the inferior problem in the whole depression ground of cage, to safeguard traffic, avoids having an accident.

For achieving the above object, the utility model is taked following design scheme: a kind of anti-theft and turnover preventing manhole cover device, include a well lid, and this well lid is provided with more than one concavo-convex geosynclinal block, and this concavo-convex geosynclinal block has the face of seizing on both sides by the arms that opens and closes as suspender.

The face of seizing on both sides by the arms of described concavo-convex geosynclinal block is a kind of of vertical plane, inclined plane.

The described face of seizing on both sides by the arms is for having anti-skid structure, former one of the face of holding under the arm that manufactures; Described anti-skid structure is anti-slip tank or matsurface blade tooth, and blade tooth is shaped as taper or rhombus, pointed, concavo-convex geometry.

Wherein, this concavo-convex geosynclinal block is shaped as in circle, rectangle, triangle, polygon or the annular any.

Described concavo-convex geosynclinal block is the prone blind hole of well lid, in be perfused with nonmetal filler, the well lid face scribbles nonmetal preservation blends layer.Or this concavo-convex geosynclinal block is well lid towards last tongue piece, the interior filler that flushes steel concrete, steel fiber reinforced concrete structure intensity with the road surface that pours into of the groove that each tongue interblock forms.

Described tongue piece is seized on both sides by the arms and is had the mouth groove that will place lifting rope on the face, as the face of holding that hangs that hangs the lid that drives a well, clamps the face of seizing on both sides by the arms for clamp.

Wherein, this well lid bottom edge place be provided with one or more down to lower extension member, corresponding fill-in well seat location retaining hoop is waled with can not stolen and escape.

Described anti-skid structure is matsurface, asperities face or former one of the face that causes naturally.

Described well lid is the circle that constitutes of monomer or many bodies, square, rectangle, polygonal body.

The manufacturing raw material of described well lid adopt metal material or high strength nonmetals.The manufacturing process of this well lid can adopt technologies such as casting, forging structure welding and machining.Well lid can't be by the deathwatch because of not opening origin of force.

The utility model has the advantages that:

1, well lid tool anti-theft feature: well lid is not opened origin of force, and has location retaining to wale, and only use special tool and just can open under vertical, EQUILIBRIUM CONDITION, thereby the thief can't open at all.

2, well lid uses and has tight security: have the location retaining to wale, well lid can't be beated, and has prevented the well lid escape.

Description of drawings

Fig. 1 is for having the block diagram () that well lid is beated or ejected manhole cover base on the road surface now

Fig. 2 is for having the block diagram (two) that well lid is beated or ejected manhole cover base on the road surface now

Fig. 3 beats for existing well lid or ejects manhole cover base block diagram (three) on the road surface

Fig. 4 is the schematic diagram that manhole cover base on the ejection road surface is beated or impacted by back wheels of vehicle to existing well lid

The block diagram (one) that Fig. 5 rotates the manhole cover base that flies out for existing well lid

The block diagram (two) that Fig. 6 rotates the manhole cover base that flies out for existing well lid

The block diagram (three) that Fig. 7 rotates the manhole cover base that flies out for existing well lid

The block diagram (four) that Fig. 8 rotates the manhole cover base that flies out for existing well lid

The block diagram (five) that Fig. 9 rotates the manhole cover base that flies out for existing well lid

Figure 10 is the three-dimensional cutaway view of the utility model well lid

Figure 10 A is the stereogram of the utility model well lid

Figure 10 B is the stereogram (another embodiment) of well lid of the present invention

Figure 11 A is the vertical view of the utility model well lid

Figure 11 B is the upward view of the utility model well lid

Figure 11 C is the sectional view of the utility model well lid

Figure 11 D is the blind hole partial sectional view of the utility model well lid

Figure 12 A to Figure 12 D is the embodiment schematic diagram of the various geometries of the utility model well lid blind hole

Figure 13 is the utility model well lid and the complete structure cross-sectional schematic of manhole cover base assembling

Figure 13 A is the start schematic diagram of Figure 13

Figure 14 A to Figure 14 E be the utility model well lid down to lower extension member different shape embodiment schematic diagram

Figure 15 A to Figure 15 E be the utility model well lid down to the embodiment of lower extension member shape of cross section schematic diagram

Figure 16 is the combination schematic perspective view of well lid of the present utility model and manhole cover base

Figure 17 is the clamping well lid schematic diagram of the utility model separate case clamp

Figure 18 is the clamping well lid cross-sectional schematic of the utility model separate case clamp

Figure 19 is the utility model operational applications schematic diagram

Figure 20 is the utility model second embodiment schematic diagram

Figure 20 A is the another example structure schematic diagram of the utility model (section)

Figure 20 B is the described well lid fill-in well of a Figure 20 A illustrated embodiment seat view

Figure 21 is the utility model second embodiment breakdown schematic diagram

The specific embodiment

See also Figure 10, Figure 10 A and Figure 11 A to Figure 11 D, the utility model anti-theft and turnover preventing manhole cover device first embodiment, it includes a well lid 1, this well lid 1 is provided with several blind holes 11, and including one at least, this blind hole 11 seizes face 111 and bottom surface 112 on both sides by the arms, this is seized face 111 on both sides by the arms and is advisable with a vertical plane in principle, and in preferred embodiment, this seizes face 111 on both sides by the arms is that to tilt and have a α angle inclined plane inwardly or outwardly be good slightly to be one, shown in Figure 11 D, must on this vertical plane or inclined plane, set up anti-skid means such as a matsurface or asperities face more in case of necessity, it is better to make clamp seize active force on both sides by the arms to it, that is this is seized on both sides by the arms and can be provided with on the face 111 with anti-skid means such as matsurface or asperities faces, in order to it is the firm effect of clamp to its clamping, so aforementioned alleged α angle of seizing face 111 on both sides by the arms is not to be imperative in practical operation, visual actual needs is accepted or rejected it; This bottom surface 112 is incorporated into the body of this well lid 1, and makes this blind hole 11 non-through these well lid 1 body thickness, and this blind hole is seized face 111 on both sides by the arms and 112 of bottom surfaces are a clear space to this, promptly is not provided with other barrier member on this blind hole.The opening geometry of this blind hole 11 can have multiple, circle, rectangle, triangle or polygon shown in Figure 12 A to Figure 12 D.This blind hole 11 is perfused with other fillers such as fluid sealant, gypsum in after installing is finished, filler is sneaked into the antirust mixture with the same color of well lid, make this filler solidify back and the same color of well lid, from being difficult for the differentiation of discovery in appearance, to reduce the chance that stealer is stolen with well lid 1.Even stealer is found the different shape of filler, but remove this filler and also will spend some times, and need there be the utility model people to apply for the special-purpose well cover opening device of special type on record on the same day, can under equilibrium conditions, vertically slings or balance is vertically mentioned, otherwise can't open well lid.

This place of keeping to the side, well lid 1 bottom surface have several down to lower extension member 12, this down to lower extension member 12 is embedded in location retaining hoop 21 on the manhole cover base 2 in order to plant in (as shown in figure 13), this well lid 1 is positioned in this manhole cover base 2.Above-mentioned each down between lower extension member 12, all leave clearance space, weigh staff foot with preventing well cover 1 wounded when the operation, make attentively operation of staff.Shown in Figure 10 B, the well lid edge is positioned at the extended element both sides can respectively open a recess 12 ' that is used to strengthen chucking power, and the retaining hoop is outer on the supporting surface in the manhole cover base wales more to be inserted in use.That this structure has is antitheft, anti-escape, anti-displacement, fall arrest, noiseproof, the whole depression of anti-skidding, anti-cage ground, to safeguard traffic, function such as avoid having an accident, also can suppress to impose on when advancing the compressive force and the drag force of well lid, avoid well lid to produce rotation and the accident of jumping out the road surface takes place because of vehicle.

Should be illustrated around here be the above-mentioned well lid 1 of the utility model be not with this down plant to lower extension member 12 that to be embedded in the location retaining hoop 21 on the manhole cover base 2 be necessity, in every case have hold this down to the location retaining hoop of lower extension member 12 in this manhole cover base, inlay card is lived, escape never, add again and do not open origin of force on the well lid, all belong to feasible.

See also Figure 13, Figure 13 A, this down form the 3rd limit RB (or FB) of inclination to lower extension member 12 summit B and well lid 1 front end R (or rear end F), according to complete formula theorem theory:

RB ²=RA ²+ AB ²So $\stackrel{\&OverBar;}{\mathrm{RB}}>\stackrel{\&OverBar;}{\mathrm{RA}}>\stackrel{\&OverBar;}{R_1{\mathrm{<figure-callout\; id="1"\; label="F"\; filenames="Y20052001602700142.png,Y20052001602700181.png"\; state="\{\{state\}\}">F</figure-callout>}}_1}$ (manhole cover base internal diameter)

So when the spreading of vehicle front-wheel when R holds, built in being manhole cover base 2 to lower extension member 12 length A B and suppressing down of well lid 1, natural inhibiting manhole cover 1 jumps out of in advance.

Shown in Figure 14 A to Figure 14 E, this shape to lower extension member 12 down can be selected taper, rectangle, abnormity, straight hook-type, crotch shape or other geometry.And for example shown in Figure 15 A to Figure 15 E, the shape of the cross section of this extended element 12 down can be rectangle, trapezoidal, circular, triangle, polygon or other geometry.

Continue and see also Figure 16 to Figure 19, this well lid 1 of the utility model is positioned on this manhole cover base 2, these manhole cover base 2 usefulness bolts 22 are fixed on the manhole cover base outside and constitute 5 places, cage basis, other mixtures such as the bar construction concrete 51 on this manhole cover base 2 and this manhole cover base basis 5 or steel fibre mixture in advance precasting together, seam 52 places in crack scribble cementing agent and whole complete combination and this manhole cover base basis 5 combines also therebetween with wellhole neck concave-convex surface.Taking-up mat one clamp 3 of this well lid 1 is held on the face of seizing on both sides by the arms 111 of blind hole 11 of this well lid 1, and this clamp 3 is located at a suspension bracket 4 bottoms, and the operation of this suspension bracket 4 of mat and clamp 3 can vertically be taken out this well lid 1 evenly.

Continue and see also Figure 20 and Figure 21, be anti-escape device second embodiment of the utility model manhole cover anti-theft, the difference of the present embodiment and first embodiment is that the face of seizing on both sides by the arms of the concavo-convex geosynclinal block of first embodiment is a blind hole for being arranged with towards the well lid below, and the concavo-convex geosynclinal block of present embodiment is the tongue piece, the face of seizing on both sides by the arms of tongue piece then is convexly equipped with towards the well lid top, both play the same tune on different musical instruments, it includes a well lid 6 well lid of present embodiment, be to be provided with a plurality of tongue pieces 61 on this well lid 6,62, groove (the concave surface 60 that each tongue interblock forms, 63,64 etc.) can irritate flat steel concrete, steel fibrous concrete, high compressive resistance strength structure thing, the degree of difficulty that is stolen with increase and keep the degree of flushing on road surface.Height fall between convex surface and concave surface is formed with the face of seizing on both sides by the arms 65,66 respectively, in other embodiments, utilizes the suitable laying of this male and fomale(M﹠F) can make this seize the position that face 65,66 is positioned at these well lid 6 different azimuth on both sides by the arms.This seizes face 65,66 on both sides by the arms, but the operation of aforementioned this suspension bracket 4 of mat and clamp 3 and this well lid 6 is vertically taken out evenly.The shape of this tongue piece can be circle, rectangle, triangle, polygon or annular projection.This tongue piece is seized on both sides by the arms and can be had the mouth groove of placing lifting rope (as reinforcing bar) on the face again, and shown in Figure 20 A, Figure 20 B, this mouthful groove can be clamped the face of seizing on both sides by the arms for clamp as the face of holding that hangs that hangs the lid that drives a well, and slings by support when lifting.

Well lid described in the utility model be its feather edge be in add when making system down to lower extension member 67, this being positioned a manhole cover base inwall to lower extension member 67 and supporting the location retaining hoop (shown in preceding embodiment) that extend on the top of anchor ring or bottom or isoplanar down, thereby the 3rd limit of formation inclination, make its 3rd limit greater than this manhole cover base diameter, nature can suppress well lid and jump out of, though suppressing well lid jumps out of, but add the strength that the location retaining hoop in the well seat blocks, well lid is ventricumbent promptly definitely can't escape to lower extension member, beat, add and do not open origin of force on the well lid, also more can't open.And safe and practical natural inhibiting type well lid is provided, and reformed and colluded the way that well lid can be opened now, eliminated well lid to be stolen easily, again the shortcoming of easy escape.And this well lid front has the blind hole that several need vertically be mentioned, and generally colludes tool, reinforcing bar, steel wire and can't suspend in midair, can slip out.And because of being perfused with homochromy filler such as fluid sealant in this blind hole, make this filler solidify back and the same color of well lid, make the surface that forms no any hole on the well lid face.By this kind method, allow stealer be difficult for from the blind hole position of realizing well lid in appearance, stealer does not know which kind of mentions the instrument of hanging and steal, adopt general instrument also can't steal the behavior of well lid or manhole cover base, like this because of the origin of force of no breakdown on the well lid, so well lid and manhole cover base just can't be stolen.

Above-listed detailed description is specifying at a possible embodiments of the present utility model; but this embodiment is not in order to limit scope of patent protection of the present utility model; allly do not break away from the equivalence that the utility model skill spirit does and implement or change, all should be contained in the utility model protection domain.

Claims (11)

1, a kind of anti-theft and turnover preventing manhole cover device includes a well lid, it is characterized in that: this well lid is provided with more than one concavo-convex geosynclinal block, and this concavo-convex geosynclinal block has the face of seizing on both sides by the arms that opens and closes as suspender.

2, anti-theft and turnover preventing manhole cover device according to claim 1 is characterized in that: the face of seizing on both sides by the arms of described concavo-convex geosynclinal block is a kind of of vertical plane, inclined plane.

3, anti-theft and turnover preventing manhole cover device according to claim 1 is characterized in that: the described face of seizing on both sides by the arms is for having anti-skid structure, former one of the face of holding under the arm that manufactures; Described anti-skid structure is anti-slip tank or matsurface blade tooth, and blade tooth is shaped as taper or rhombus, pointed, concavo-convex geometry.

4, anti-theft and turnover preventing manhole cover according to claim 1 dress stomach is characterized in that: wherein, this concavo-convex geosynclinal block be shaped as in circle, rectangle, triangle, polygon or the annular any.

5, anti-theft and turnover preventing manhole cover device according to claim 1 is characterized in that: described concavo-convex geosynclinal block is the prone blind hole of well lid, in be perfused with nonmetal filler, the well lid face scribbles nonmetal preservation blends layer.

6, anti-theft and turnover preventing manhole cover device according to claim 1, it is characterized in that: wherein, this concavo-convex geosynclinal block is well lid towards last tongue piece, and perfusion flushes the filler of steel concrete, steel fiber reinforced concrete structure intensity in the groove that each tongue interblock forms with the road surface.

7, anti-theft and turnover preventing manhole cover device according to claim 6 is characterized in that: described tongue piece is seized on both sides by the arms and is had the mouth groove that will place lifting rope on the face.

8, anti-theft and turnover preventing manhole cover device according to claim 1, it is characterized in that: wherein, this well lid bottom edge place be provided with one or more down to lower extension member, corresponding fill-in well seat location retaining hoop is waled with can not stolen and escape, and the well lid edge is positioned at the extended element both sides and respectively opens a recess that is used to strengthen chucking power.

9, anti-theft and turnover preventing manhole cover device according to claim 3 is characterized in that: wherein, this anti-skid structure is matsurface, asperities face or former one of the face that causes naturally.

10, anti-theft and turnover preventing manhole cover device according to claim 1 is characterized in that: described well lid is the circle that constitutes of monomer or many bodies, square, rectangle, polygonal body.

11, anti-theft and turnover preventing manhole cover device according to claim 1 is characterized in that: the manufacturing raw material of this well lid adopt metal material or high strength nonmetals.

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