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 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. 11/657,739, filed Jan. 25, 2007. 
    
    
     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 arcuate engagement cams that engage and hold the cutting tool within the interior casing of the manhole to be removed. A central swivel bearing allows the assembly to accommodate uneven street surfaces during use. 
    
    
     
       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 on lines  2 - 2  of  FIG. 1 . 
         FIG. 3  is a top plan view on lines  3 - 3  of  FIG. 1 . 
         FIG. 4  is a bottom plan view of the device with manhole engagement cams extended. 
         FIG. 5  is an enlarged partial top plan view of an adjustable cutting arm of the invention. 
         FIG. 6  is an enlarged side elevational view with portions broken away of a cutting blade of the invention. 
         FIG. 7  is an enlarged side elevational view with portions broken away of the adjustable manhole engagement portion of the invention. 
         FIG. 8  is a side elevational view with portions shown in section with the invention positioned within a manhole for removal. 
         FIG. 9  is a side elevational view of an alternate assembly of the manhole removing device illustrating an improved locking alignment assembly. 
         FIG. 10  is an enlarged side elevational view of the locking alignment assembly with portions broken away. 
         FIG. 11  is a top plan view of the locking alignment assembly. 
         FIG. 12  is an end plan view on lines  12 - 12  of  FIG. 10 . 
         FIG. 13  is a cross-section view on lines  13 - 13  of  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1  of the drawings, a 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. Pairs of oppositely disposed aligned cutting blade mounting arms  16 A,  16 B and  17 A and  17 B are slidably positioned between respective support frame disks  11  and  12  and some of the guide brackets  15 . Each of the mounting arms  16 A and  17 B are of a tubular construction having a plurality of longitudinally 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  18  are secured therethrough providing for incremental longitudinal adjustment of each of the mounting arms  16 A and  16 B and  17 A and  17 B extending from between the respective support frame disks  11  and  12 . To provide additional support and spacing requirements for the arms apertured reinforcement plates  19  are positioned between each of the respective arm pairs  16  and  17  and the upper support frame disk  11 . 
     Cutting blades  20  are secured to the free ends at  21  of each of the arms 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. 6  of the drawings. 
     It will be seen that by adjustably repositioning the mounting arms  16 A and  16 B and  17 A and  17 B equally the effective cutting diameter of the attached cutting blades  20  when driven circularly in respect of the diameter of a manhole  23  to be removed as seen graphically in  FIG. 8  of the drawings and will be described in greater detail hereinafter. 
     Referring now to  FIGS. 1 ,  3 ,  4  and  5  of the drawings, a locking alignment assembly  24  is provided on a main support shaft  25  in spaced vertical relation to the main support frame disks  11  and  12  for engagement within the interior I of the manhole  23  to be removed. The locking and alignment assembly  24  has a pair of circular mounting plates  26  and  27  with multiple extendable cam elements  28 A,  28 B,  28 C, and  28 D pivotally secured therebetween. 
     The upper mounting plate  26 , best seen in  FIG. 3  of the drawings, has a central aperture with an upstanding transfer collar  29  thereabout and a series of arcuate cam adjustment slots  30 A,  30 B,  30 C and  30 D therein. The cam elements  28 A,  28 B and  28 C are pivotally secured to the lower plate  27  via pivot attachment pins  31 , best seen in  FIG. 4  of the drawings. 
     Adjustment deployment guide bolt assemblies  32  extend from each of the cam elements  28  and are slidably disposed within the corresponding adjustment slots  30 A,  30 B,  30 C and  30 D as hereinbefore described. The upper mounting plate  26  has contoured activation access notches  33 A and  33 B while the lower plate  27  has oppositely disposed notch pairs  34 A and  34 B and  34 C and  34 D to accommodate the pivoted displacement of the respective cam elements  28  as shown in broken lines in  FIG. 3  of the drawings. 
     Referring now to  FIGS. 9-13  of the drawings, an alternate improved alignment locking assembly  35  can be seen that will be positioned on the main support shaft  25  of the cutting device in the same spaced orientation within the assembly as that of the primary locking and alignment assembly  24  as hereinbefore described. 
     The alternate alignment and locking assembly  35  has a main support frame  36  with spaced parallel guide tube pairs  37  and  38  secured on a mounting platform  39  as best seen in  FIGS. 11 and 13  of the drawings. Apertured base plates  40  and  41  extend between and are secured to the inner facing tubes  37 A and  38 A of the respective guide tube pairs  37  and  38 . 
     A pair of adjustable manhole engagement arm assemblies  42  and  43  are slidably disposed from within the respective guide tube pairs  37 A and  38 A and  37 B and  38 B respectively. 
     Each of said engagement arm assemblies  42  and  43  are secured to one another by reinforcing plates  45  and  46  having respective threaded rods  47  and  48  adjustably extending therethrough. The threaded rods extend from and are fixed to the respective aperture base plates  40  and  41  as hereinbefore described. 
     Locking nuts  49  are threadably positioned on the respective rods  47  and  48  engaging the corresponding plates  45  and  46  allowing for longitudinal repositioning of their interconnected engagement arm assemblies  42  and  43  from within the hereinbefore described guide tube pairs  37  and  38 . 
     The arm assemblies  42  and  43  comprise tubular arm elements  42 A and  42 B and  43 A and  43 B respectively each of which has an upstanding engagement tab  49  inwardly from their respective free ends as best seen in  FIGS. 9 and 10  of the drawings. The engagement tabs  49  are angled outwardly with a surface engagement tab portion  49 A which is in end surface co-planar vertical alignment with a corresponding perimeter end surface S of the arms so as to equally engage the aligned inner surface of the manhole indicated at  50  in broken lines in  FIG. 11  of the drawings. 
     A cross support rod  51  extends between respective arm assembly engagement tabs  49  with additional support imparted to the respective arm pairs  42 A,  42 B,  43 A and  43 B by multiple reinforcement gussets pairs  52  and  53  as will be well understood by those skilled in the art. A handle  54  is secured to the guide tube pairs  37  and  38  for transport positioning thereof. 
     A critical aspect of the invention is to provide for adapted use to street environments is a swivel bearing  35  which is secured to the lower mounting plate  27  which will accommodate the angular inclination of the manhole when mounted within as illustrated in  FIG. 8  of the drawings. 
     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 a hydraulic power drive 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 and the multiple cutting blades  20  are adjusted using the locking nut and bolt assemblies  18  to advance or retract the respective mounting arms  16 A and  16 B and  17 A and  17 B in equal increments. The manhole removal tool  10  of the invention is positioned over the manhole  23  as best seen graphically in  FIG. 8  of the drawings and lowered with the locking alignment assembly  22  or alternate  35  are adjustably engaged within the interior surface I of the manhole  23  by the extension and engagement in assembly  22  of the hereinbefore described cam elements  28  by use of the deployment guide bolt assemblies  32  within the respective slots  30 A,  30 B,  30 C and  30 D or adjustable arm assemblies  42  and  43 . As noted, the swivel bearing  31  allows for angular inclination therewith so that the cutting assembly can properly engage the street surface SS which may be of an angular inclination in relation to the orientation of the manhole. 
     In use with the alternate alignment and locking assembly  35  is positioned on the cutting tool shaft  25  which is then positioned within the open manhole  23 . The adjustable engagement arm assemblies  42  and  43  are advanced by rotation of the respective thrust locking nuts  49  on the corresponding threaded rods  47  and  48  with the corresponding upstanding engagement elements  49  thereon frictionally engaging the inner surface  50  of the manhole  23  as noted securing same thereto for removal once the surrounding pavement material has been continuously cut. 
     As the manhole removal tool  10  is rotated by the power take-off (not shown) the respective support disks  11  and  12  having the multiple extending cutter assemblies  20  thereon will engage and cut into the street surface SS defining a circular cut in spaced relation about the diameter of the manhole  23  to a predetermined depth. The manhole removal tool  10  then removes the manhole  23  and surrounding surface material allowing for preparation and installation of a new manhole assembly by multiple installation step as will be well known and understood by those skilled in the art. 
     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 may be made thereto without departing from the spirit of the invention.