Abstract:
A device to secure, cut and sequentially remove a manhole from a street environment. The manhole removing device is supported and rotatably driven hydraulically by a mobile operation equipment. A circular disk assembly has adjustable pavement cutters adjustably positioned from there within an inter-related manhole centering and a locking alignment and engagement plate assembly define a one-step cutting and removal of an existing manhole from the street for replacement.

Description:
This is a continuation in part application of Ser. No. 11/900,583, filed Sep. 13, 2007 now U.S. Pat. No. 7,740,415. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This device relates to automated digging machines that have been developed to engage, cut and remove manholes found in street environments. Such machines typically cut the interior casing of the manhole in preparation for removal, repair and replacement due to changes in street elevations associated with resurfacing or repair and replacement. 
     2. Description of Prior Art 
     Prior art devices of this type have relied on a variety of cutting and removal devices, see for example U.S. Pat. Nos. 4,924,951, 4,968,101, 5,470,131, 6,536,987, 6,709,064 and 6,755,481. 
     U.S. Pat. No. 4,924,951 claims a manhole cutter for cutting a fixed diameter circular groove of a fixed depth around the surface of a manhole. The cutter is of a continuous ring design with spaced sections having cutting teeth elements. 
     A vertical asphalt and concrete milling device is illustrated in U.S. Pat. No. 4,968,101 having a large circular cutting drum with continuous teeth along the bottom edge. 
     In U.S. Pat. No. 5,470,131 a method and apparatus for cutting circular slots in pavements extending about a manhole casing is disclosed in which a self-propelled core cutting device has an open drum shaped cutting blade which is rotated by a hydraulic drive means to engage and cut the surface about an existing manhole. 
     U.S. Pat. No. 6,536,987 discloses a quick manhole/manhole construction method and related device in which a cutting unit is positioned within the manhole and the cuts using a circular saw for removal thereof. 
     U.S. Pat. No. 6,709,064 is directed towards a method and device for detaching or cutting an embedded manhole frame that positions a circular cutting saw blade within the manhole so as to cut from the inside the existing hole casing for removal. 
     U.S. Pat. No. 6,755,481 claims a method for cutting asphalt or concrete around a manhole using a circular offset cutting blade. 
     SUMMARY OF THE INVENTION 
     An automatic manhole removing tool for use with a mobile power take-off that cuts and removes a manhole assembly from a street surface for replacement. The tool self-centers and secures within the manhole using adjustable blade elements to cut a circular groove about the manhole and therein remove same. An adjustable manhole engagement assembly provides multiple adjustable engagement arm pairs that engage the manhole frame aligning the cutting tool within the interior casing of the manhole to be removed. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevational view of the manhole removing device of the invention. 
         FIG. 2  is a top plan view thereof. 
         FIG. 3  is an enlarged partial top plan view of an adjustable cutting arm of the invention. 
         FIG. 4  is an enlarged side elevational view with portions broken away of a cutting blade of the invention. 
         FIG. 5  is a side elevational view illustrating a locking alignment assembly. 
         FIG. 6  is a top plan view of the locking alignment assembly. 
         FIG. 7  is a cross-section view on lines  7 - 7  of  FIG. 6 . 
         FIG. 8  is a side elevational view with a portion broken away of the manhole removal device with an alternate cutting blade and alternate locking alignment device. 
         FIG. 9  is a top plan view of an alternate locking alignment assembly. 
         FIG. 10  is an enlarged side elevational view thereof with portions broken away. 
         FIG. 11  is an enlarged end elevational view. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1  of the drawings, an improved manhole removal tool  10  of the invention can be seen having a pair of vertically spaced and aligned main support frame disks  11  and  12  secured to a central drive shaft assembly  13 . The upper disk  11  has a reinforced plate  14  with a plurality of interconnection and guide brackets  15  extending between and securing the support frame disks  11  and  12  together. Multiple reinforcement gussets  16  are welded to the reinforcement plate  14  and central drive shaft assembly  13 . A drive and extraction shaft  13 A extends from the shaft assembly  13 . Pairs of oppositely disposed aligned cutting blade mounting arms  17 A,  17 B and  18 A and  18 B are slidably positioned between respective support frame disks  11  and  12  and the respective guide brackets  15 . Each of the mounting arms  17 A and  18 B are of a tubular construction having a plurality of longitudinally spaced and transversely aligned adjustable adjustment apertures A therein with a pair of spaced corresponding apertures A 1  in their respective upper and lower support frame disks  11  and  12 . Locking nut and bolt assemblies  19  are secured therethrough providing for incremental longitudinal adjustment of each of the mounting arms  17 A and  17 B and  18 A and  18 B extending from the respective guide brackets  15  between support frame disks  11  and  12 . Each of the mounting arms  17 A and  17 B and  18 A and  18 B have an apertured mounting flange  20  on the free end thereof. 
     Cutting blades  21  are secured to the mounting flanges  20  by multiple nut and bolt assemblies  19 A with of each of the blades extending downwardly therefrom with a plurality of hardened cutting teeth  22  which are welded in longitudinally spaced relation to one another on each of the arms oppositely disposed ends thereof as best seen in  FIG. 4  of the drawings. 
     The mounting arms  17 A and  17 B and  18 A and  18 B determines the effective cutting diameter of the attached cutting blades  20  when driven circularly in respect of the diameter of a manhole MH to be removed as seen graphically in  FIG. 1  of the drawings and will be described in greater detail hereinafter. 
     It will be seen that the respective support frame disks  11  and  12  have oppositely disposed reduced edge diameter portions  11 A and  12 A above and below the respective mounting arms  17 A,  17 B and  18 A and  18 B to provide additional adjustment clearance therefore when fully retracted therebetween. 
     Referring to  FIGS. 1 and 2  of the drawings, an integrated leg support assembly  23  for the manhole removal tool  10  when not in use can be seen having multiple annular leg receiving sockets  24  affixed between the frame disks  11  and  12 . Each of the leg sockets  24  are aligned with access openings  25  in the disk  12  and evenly spaced between the respective adjustable cutting blade mounting arm pairs  17 A,  17 B and  18 A and  18 B hereinbefore described. 
     Tubular leg extension portions  26  of a reduced diameter are slidably secured within the respective sockets  24  by pins P through aligned receiving apertures A inwardly of the respective ends. Leg portion receiving platforms  27  are provided having a ground engagement end plate  28  secured on one end and are positioned and sized so as to telescopically receive the respective leg portions  26  which in combination provide a stable elevated integrated support structure for the manhole removal tool  10  when not in use. 
     Referring now to  FIGS. 5 ,  6  and  7  of the drawings, an improved alignment locking assembly  29  can be seen that will be positioned to receive a main support shaft  30  of the drive shaft assembly  13 . 
     The improved alignment and locking assembly  29  has a main support frame  31  with spaced parallel guide tube pairs  32  and  33  secured on a mounting platform  34  as best seen in  FIG. 6  of the drawings. Apertured plates  35  and  36  extend between and are secured to the inner facing tubes  32 A and  33 A of the respective guide tube pairs  32  and  33 . 
     A pair of movable manhole engagement arm assemblies  37  and  38  are comprises of tubular elements  37 A,  37 B,  38 A and  38 B respectively and are slidably disposed from within respective guide tube pairs  32  and  33  extending in oppositely disposed relation to one another. 
     Each pair of said tubular elements  37 A,  37 B,  38 A and  38 B are secured to one another adjacent their respective free ends by reinforcing plates  39  and  40  with the plate  39  having a central aperture therein. A threaded adjustment rod  41  extends from and is secured to the respective apertured base plate  39  by a separate mounting plate  39 A. An indexed apertured adjustment disk  42  is threaded on the threaded rod  41  in spaced relation to the mounting plate  39 A. The threaded rod  41  extends through an aperture A in the plate  39  so as to allow rotational adjustment of the disk  42  therealong so as to be positioned against the plate  39  advancing the arm assembly  37  from within the respective guide tube pair  33 . 
     A locking disk engagement hook  43  is slidably mounted on the plate  39  for selective engagement through the apertured adjustment disk  42 . This allows for longitudinal fixed repositioning of the arm assembly  37  from within the hereinbefore described guide tube pair  33  as indicated in broken lines in  FIG. 6  of the drawings. 
     The corresponding movable manhole engagement arm assembly  38  has a plurality of longitudinally spaced apertures A therein for registration insertion of a locking pin P through a correspondingly selectively aligned aperture A in the guide tube pair  33  so as to effectively lock the engagement arm assembly  38  in a preselected extended position relative to the guide tube pairs  33  as best seen again in  FIG. 6  of the drawings. 
     The tubular elements  37 A,  37 B,  38 A and  38 B of the respective arm assemblies  37  and  38  each have an upstanding adjustable L-shaped manhole engagement tab  44  positioned inwardly from the respective free ends, as best seen in  FIGS. 5 and 6  of the drawings. The adjustable engagement tabs  44  are vertically adjustable in height by alignment with registering apertures in adjacent mounting plates  45  positioned on the respective tubular elements with nut and bolt fasteners F as seen in broken lines in  FIG. 5  of the drawings. 
     The engagement tabs  44  extend outwardly with a surface engagement tab portion  45  beyond corresponding perimeter end surface S of the respective tubular elements  37 A,  37 B,  38 A and  38 B which are positioned for engagement with the inner surface of the manhole MH indicated graphically in broken lines in  FIG. 6  of the drawings. 
     The reinforcement plates  39  and  40  that extend between respective arm assemblies are adjacent the engagement tabs  44  with additional support imparted to the respective arm pairs by reinforcement gusset pairs  46  as will be well known and understood by those skilled in the art. Additionally, handles  47  and  48  are provided which are secured to and between the respective tubular elements  37 A,  37 B,  38 A and  38 B for transport and positioning thereof. 
     In use, the manhole removal tool  10  of the invention is connected to a mobile power equipment (not shown) like a backhoe or Bobcat type loader having hydraulic power take-off which is well known and understood by those skilled in the art. The effective diameter of the cut to be made about the manhole is determined by the multiple cutting blades  20  which are adjusted using the locking nut and bolt assemblies  18  to advance and retract the respective mounting arms  17 A,  17 B,  18 A and  18 B in equal increments. 
     Referring now to  FIG. 8  of the drawings, an alternate offset cutting blade assembly  49  can be seen broken away in which the blade  50  has a right angular offset reinforced portion  51  with a depending surface engagement blade portion  52  extending therefrom. This allows for reduced diameter cuts which may be required in certain environments by reducing the effective diameter of the cutting blades by the proportional offset positioning of the blade  50  in association to that of the respective mounting arm. 
     In use, the alignment and locking assembly  29  is positioned within an open manhole MH with the movable manhole engagement arm assemblies  37  and  38  are adjusted and locked in place by advancement and rotation of the disk  42  on the corresponding threaded rod  41  with the corresponding perimeter end surfaces S of the arms frictionally engaging the inner surface of the manhole MH, as noted securing same thereto for removal once the surrounding pavement material has been continuously cut. The manhole removal tool is then positioned over the manhole MH and lowered with the drive shaft  13 A extending through a key-shaped opening in the best base plate  39  of the locking and alignment assembly  37  as seen graphically in  FIG. 1  of the drawings. The drive shaft  13 A has multiple spaced key ways  52  therethrough with a selectively insertable single key tab  53 . 
     As the manhole removal tool is rotated by the power take-off (not shown) the respective supporting disks  11  and  12  having the multiple extended cutter assemblies  20  thereon will engage and cut into the street surface SS defining a circular cut of a greater diameter than that of the manhole MH to a predetermined depth. The manhole removal tool  10  then removes the manhole MH and surrounding surface material by retracting the tool  10  and the engagement of the drive shaft key lift tab  53  in non-alignment with the key opening so as to lift the locking and alignment assembly  29 , the manhole MH and associated material thereabout up and outwardly from the street leaving a uniform opening in the street which allows for rebuilding of the manhole MH to its proper height. 
     Referring now to  FIGS. 9 and 10  of the drawings, an alternate alignment and locking assembly can be seen at  54  to address manhole configurations that require the alignment and locking assembly to be wedgeably engaged within the manhole casting. 
     A pair of oppositely disposed expanding arcuate engagement band assemblies  55  and  56  are adjustably secured to one another extending from the respective free ends of modified tubular extension arm assemblies  57  and  58  as will be described in detail hereinafter. 
     The arm assembly  57  has arm tubes  57 A and  57 B, each of which have cam roller mounting assemblies  58 A and  58 B on their free ends thereof. A transverse interconnecting support plate  59  with an upstanding apertured flange  60  extends between the tubes  57 A and  57 B adjacent the respective cam roller mounting assemblies  58 A and  58 B. 
     Correspondingly, the oppositely disposed arm assembly  58  has extending tubes  61 A and  61 B with their own cam roller mounting assemblies  62 A and  62 B extending from their respective free ends. 
     The arms assemblies  57  and  58  are slidably disposed from within corresponding spaced parallel guide tube pairs  63  and  64  secured to one another in spaced parallel relation with interconnecting ribs  65  and  66  extending therebetween defining a key way fitting  67  therebetween. 
     The respective cam roller mounting assemblies  57 A,  57 B,  62 A and  62 B have a U-shaped linkage arm  68  that is secured to the corresponding engagement band assemblies  55  and  56  so as to be vertically movable against the respective cam roller assemblies during engagement. The arm assembly  58  is movable from a first retracted position within the guide tube pairs  64  to a second fully extended position and locked by aligned fasteners F therethrough as best seen in  FIG. 9  of the drawings. 
     The arm assembly  57  is incrementally advanced by engagement with an adjustment disk  69  which is rotatably positioned on a threaded rod  70  extending from the spacing rib  65  through the aperture in the flange  60  as hereinbefore described. It will thus be seen that by rotation of the disk  69 , it will advance and engage the flange  60  incrementally extending the arm assembly  57  outwardly from its respective guide tube pairs  63  thus advancing the interlinked band assembly  55  against the inner surface of a manhole MH during use. Once adjustment has been achieved of the arm assembly  57  an offset indexing bar  71  slidably positioned in a bracket on the flange  60  can selectively engages and locks the adjustment disk  69  by registration with the aligned annularly spaced apertured therewithin. 
     Referring to  FIG. 9  of the drawings, the manhole engagement bands  55  and  56  each have a curved center band  55 A and  56 A with apertured ends  55 B and  56 B. Each of the bands accordingly have a pair of arcuately spaced frictional engagement plates  72  and  73  secured thereon for direct engagement with the inside surface of the manhole MH. The curved center bands  55 A and  56 A are adjustably secured together by interengaging threaded adjustment couplings  74  and  75  having apertured bifurcated end brackets  74 A and  75 A on the respective apertured band free ends  55 B and  56 B by pivoted fasteners F therethrough. The adjustable combination allows for manhole insertion and adjustment retention therewithin by expansion compression of the bands by the respective arm assemblies  55  and  56  as hereinbefore described. 
     Multiple retainment positioning tabs  76  are mounted on the outer surface S of the respective bands  55 A and  56 A allowing the alternate alignment and locking assembly  54  to be positioned initially in the manhole MH before the extension of the respective arm assemblies and interlinked pivoting engagement band assemblies  55  and  56  securely lock the assembly in place within the manhole. 
     The wedging action will accommodate manhole configurations without internal flanges which would be normally engaged by the primary alignment and locking assembly tubular arm assemblies  37  and  38  as hereinbefore described. 
     It will be evident from the above description that the alternate alignment and locking assembly  54  will provide centering guidance to the improved manhole removal tool  10  in which the drive shaft  13 A is extended through the key way  67  for guidance and then after surface cutting has occurred around the manhole MH, the repositioning of the drive shaft so as to engage the lift tab  53  within the key way  67  allows for removal of the manhole and associated cut-out of the street surface thereabout by elevation of the removal tool  10  by the mobile power equipment which it is attached (not shown) as previously described and disclosed. 
     It will thus be seen that a new and novel manhole removal tool  10  of the invention has been illustrated and described and it will be apparent to those skilled in the art that various changes and modifications will be made thereto without departing from the spirit of the invention. Therefore I claim: