Abstract:
A collar for supporting or protecting pipes on an outside drop adjacent a manhole is provided. A plurality of stacked collar sections can protect pipes comprising the outside drop. Alternatively a plurality of collar segments having a circular wall within can form the pipe integrally with the collar. The collars can protect riser pipe sections or elbow piper sections. The collars may be split for ease of installation around pipes and fastened together around the pipe. The collars are easily attached to the manhole by drilling a hole into the manhole at designated places and using bolts through tabs on the collars to hold the collar in place adjacent the manhole. The collars can have several different standard heights and be stacked to the desired height of the manhole. Pipes having riser sections or elbow sections can have protective collars.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a collar attached to the side of a manhole to protect an outside drop adjacent the manhole, and alternatively for the plurality of collars to form a protected outside drop. 
     2. Description of the Related Art 
     When an outside drop is used adjacent a manhole the outside drop is subject to damage and subsequent leaks by rocks and other fill material and due to shifting of the ground, the weight of the pipes and other factors. It is desired to have a protective collar around the drop pipe. 
     Currently protective collars are very heavy which makes them difficult and expensive to transport and install. The protective collars in use need to be set on a solid base as part of the base of the manhole, which makes the manhole itself heavier, more expensive and more difficult to install in the ground. The collars surround a drop pipe must be made the correct size to support the drop pipe, collars and connections, particularly at the top of the outside drop where there is a T connection and at the bottom of the outside drop where there is an elbow pipe connection. Since riser collars are made of concrete they are very heavy and require tools to lift the collar parts into place. Since the riser collars are not fastened to the manhole they may have gaps between the manhole and the collar or may shift way from the manhole. 
     Outside drop pipes are generally made from ductile iron, which is heavy, expensive and hard to work with. Plastic pipe is lighter, costs less, is easier to connect and easier to work with. However plastic pipe is more subject to damage and needs protection. 
     SUMMARY OF THE INVENTION 
     A lightweight easy to install protective collar is attached to the side of a manhole to surround an outside drop while securing the outside drop in place adjacent the manhole. The protective collar can be one or more sections separated by some distance or the sections can be stacked to form a continuous protective barrier. The collar can form around an outside drop pipe or the collars can have an opening therein to form the outside drop pipe inside the collar. The diameters of the pipes on the outside drop can be standardized by using expansion or reduction pipes at the top or bottom of the manhole so that only one size protective collar needs to be used. Similarly with a combination internal pipe and collar only one size internal pipe needs to be produced when expansion and contraction collar sections are used. The collars can fit over expansion or reduction pipes and over elbow pipes. The collars with integral pipes can fit around expansion or reduction internal pipes and elbow pipes, and can have expanded portions for fitting over pipe coupling segments and flanges. The collars for fitting over pipes can be split radially or perpendicular to radially and assembled around the pipes. The collars for fitting over pipes can have expanded portions for fitting over pipe coupling segments and flanges. 
     Tubes molded into collars and extending between opposing walls add strength to the collars, which are molded as hollow parts. To add weight and stability an aperture in the top of the collars can be used to fill the collars with sand or other material to increase the weight and impact absorbing ability of the collars. Similarly apertures in the sides of the collars can let water in if the water table rises and let water out when the water table declines. 
     OBJECTS OF THE INVENTION 
     It is an object of the invention to provide a lightweight outside drop collar. 
     It is an object of the invention to provide an easy to assemble outside drop collar. 
     It is an object of the invention to provide a low cost outside drop collar. 
     It is an object of the invention to provide an outside drop collar that attaches to a manhole. 
     It is an object of the invention to provide an outside drop collar that does not need a base on the manhole. 
     It is an object of the invention to provide a combination collar and outside drop pipe for a manhole. 
     It is an object of the invention to provide size adaptors for connecting pipe to the outside drop to standardize the size of the outside drop collar sections. 
     It is an object of the invention to provide collar sections in standard heights to fit manhole heights. 
     It is an object of the invention to provide an outside drop collar with apertures for letting water in or out of the collar. 
     It is an object of the invention to provide an outside drop, which can be filled to add weight and strength to the outside drop collar. 
    
    
     Other objects, advantages and novel features of the present invention will become apparent from the following description of the preferred embodiments when considered in conjunction with the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side cross sectional view of an outside drop adjacent a manhole with a single collar section. 
     FIG. 2 is a perspective view of a collar section. 
     FIG. 3 is a top view of a collar section. 
     FIG. 4 is a perspective view of a radially split collar section. 
     FIG. 5 is a top view of a radially split collar section. 
     FIG. 6 is a side cross sectional view of an outside drop adjacent a manhole with a collar enclosing the riser and elbow. 
     FIG. 7 is a perspective view of a short section of a riser collar having a radial split. 
     FIG. 8 is a perspective view of a medium section of a riser collar having a radial split. 
     FIG. 9 is a perspective view of a long section of a riser collar having a radial split. 
     FIG. 10 is a perspective view of an elbow collar having a radial split. 
     FIG. 11 is a perspective view of an elbow collar having a radial split containing an elbow pipe. 
     FIG. 12 is a side cross view of an outside drop adjacent a manhole with multiple riser sections having integral inside pipe walls. 
     FIG. 13 is perspective view of a riser section having integral inside pipe walls. 
     FIG. 14 is a perspective view of an elbow section having integral inside pipe walls. 
     FIG. 15 is a side view of a manhole with the riser having an expanding T adaptor and the elbow having a reducing adaptor. 
     FIG. 16 is a side view of a manhole with the riser having a reducing T adaptor and the elbow having an expanding adaptor. 
     FIG. 17 is a side view of an expanding T adaptor connection. 
     FIG. 18 is a side view of a reducing T adaptor connection. 
     FIG. 19 is a side view of a T collar connector. 
     FIG. 20 is a perspective view of an elbow collar with an elbow pipe and elbow reduction adaptor. 
     FIG. 21 is a perspective view of an elbow collar with an elbow pipe and elbow expansion adaptor. 
     FIG. 22 is a side view of a manhole with an outside drop having an expansion adaptive riser a reduction adaptive elbow and a protective collar. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A typical manhole  10  may be one long molded concrete pipe with openings  70 ,  71 ,  72  for outside drop pipes to connect to the manhole  10  at the top  70  and bottom  71  and for outflow  72 . The manhole may come in sections as in FIG. 1, which are assembled to form the manhole  10 . In FIG. 1 manhole  10  has three sections, a bottom section  12 , a middle section  13 , and a top section  14 . In order to facilitate working in the manhole  10  an outside drop  20  is used to add waste flowing into the sewer system. The outside drop  20  has a T connector  22  at the top, a riser section  24  and an elbow  26  at the bottom. Typically the outside drop  20  is made of ductile iron. After the manhole  10  and outside drop  20  are installed in a hole in the ground, filler materials such as rocks, sand and soil are placed in the hole to fill in the empty space surrounding the manhole  10  and outside drop  20 . If the outside drop  20  has no supports it can by its own weight move relative to the manhole  10  which may cause leaks at the joints between the T connector  22  and the riser section  24 , or between the riser section  24  and the elbow  26 , or the elbow and the manhole  10 . The outside drop  20  may also be struck by rocks in the filler material and be moved or damaged. The outside drop riser section  24  may be an assembly of two or more pipes depending on the height of the manhole  10 . The additional connections for multiple section risers are also subject to leaks at the joints if the outside drop  20  is moved or damaged. Over time ground shifts due to settling, vibrations, drainage, water tables, frost, subsidence, and other geological or man made conditions may move the outside drop  20  relative the manhole  10 . 
     In order to protect the outside drop  20  and attach it to the manhole  10  for stability, a riser collar  30  may be used. FIGS. 2 and 3 show a riser collar  30  having a front portion  32  for attachment to the manhole  10  and a rear portion  34  for attachment to the front portion  32 . In assembling the outside drop manhole in the ground the manhole  10  is inserted into the ground and then the outside drop  20  is attached. The riser collar  30  is then attached to the riser  24  to keep the outside drop  20  in place relative the manhole  10 . The riser collar  30  has a curved attachment wall  37  for mating with the outer face  15  of the manhole  10 . Tabs  35  with bolt apertures  36  are for attaching the riser collar  30  to the manhole  10  with bolts. A drill can be used to drill a hole in the manhole  10  at the proper locations for attachment of the front collar portions  32  and then bolts inserted through apertures  36  in tabs  35  to secure the front collar portions  32  to the manhole  10 . The rear portion of the collar  34  then mates with and is bolted to the front collar portion  32  by bolts extending through the bolt aperture  38  in the rear collar portion  34  to the bolt receiving section  39  of front collar portion  32 . The riser collar  30  is thus secured to the manhole  10  and surrounds and protects a portion of the outside drop  20  on riser section  24  such that it secures the riser section  24  in place and protects it from damage in the area the collar surrounds. For short collar sections the riser collar  30  may have support portions  33  for engaging the outer face  15  of manhole  10  for greater stability. 
     For ease of construction the front collar portion  32  may be attached to the manhole  10  or manhole portion  12 ,  13 , or  14  above ground. The outside drop  20  may then be added in the ground and the rear collar portion  34  assembled last. Alternatively any order of assembly may be used. 
     The collar may be split radially as in FIGS. 4 and 5 where radially split riser collar  130  has right collar portion  132  and left collar portion  134 . The riser  24  can be installed in the outside drop  20  and the riser collar  130  can be installed around the riser  24  by attaching the right collar portion  132  on the manhole  10  by bolts thought apertures  36  in tabs  35  and then attaching the right collar portion  134  to the manhole  10  by bolts though apertures  36  in tabs  35 . As before boltholes are drilled in the manhole  10  in the appropriate places. A support portion  133  may be used to help stabilize the riser collar  130  on the manhole  10 . The right portion of the collar  132  and the left portion of the collar  134  can have an engagement mechanism  131  such as a guide pin  128  and aperture  129  arrangement to guide the two halves  132 ,  134  of the radially split riser collar  130  together and hold them in place. There may also be a flange  138  on right collar portion  132  and a flange  139  on left collar portion  134  for placing a bolt or other fastener through to lock the two halves of the radially split riser collar  130  together. It is easier to install the radially split riser collar  130  than riser collar  30  around an outside drop  20  already installed on the manhole  10  because the riser collar  30  has to be installed between the manhole  10  and the outside drop  20  which may be difficult once the outside drop  20  is installed. 
     Rather than have one or two sections of protective sections of riser collars  30  or  130  along the riser  24  the collars can be installed to protect the entire length of the riser  24 . As shown in FIG. 6 riser  24  has three different length sections of stacked riser collars  50 ,  150  and  250 , which completely surround and protect the riser  24  and attach the riser  24  to the manhole  10 . 
     In the embodiments shown in FIGS. 7,  8  and  9  the riser collars  50 ,  150  and  250  respectively are radially split as is riser collar  130  but alternatively may be split in half as riser collar  30  is. Further the riser collars  50 ,  150  and  250  are shown with a pipe coupler engaging portion  52  and a pipe engaging portion  54 . The pipe coupler engaging portion  52  fits over pipe couplings between riser  24  sections or between riser  24  sections and connections to T connectors  22  or elbow connectors  24 . The short length riser collar  50  is shown in FIG. 7 with tongue  89  and groove  88  connections between the top and bottom of like kind collar sections for stacking them. The medium length riser collar  50  is shown in FIG. 8 with a nesting flange  85  over an interior raised section  84  for stacking the collar sections. The long length riser collar  250  is shown in FIG. 9 with a pin  86  and aperture  87  method of stacking the riser collars. The riser collar sections may have a pipe engaging portion  52 , or not as shown for riser collars  30 ,  130 . For the longer the riser collar sections more tabs  35  are used for bolting the collars to the manhole  10 . 
     As can be readily understood any method of stacking the collar sections together can be used and would be uniform throughout the stack. 
     The riser collars  30 ,  50 ,  130 ,  150 ,  250  are preferably made of a molded plastic. The inside of the collars are hollow making the riser collars lightweight and easy to work with. In order to simulate the heavier concrete collars of the prior art and afford more protection for the riser  24 , the collars can be filled with sand after installation to make them heavy and less prone indentation and damage. An aperture  82  in the top of the collar can be used to add sand or other filler material to the riser collar once it is installed. The riser collars  30 ,  50 ,  130 ,  150 ,  250  may also have apertures  81  in the sides of the collars at the base of the collar for water to enter and leave. As the water table in the ground rises and falls it may be beneficial to let water in so that the buoyancy of the water will not stress the collar on the manhole. Similarly if water enters the riser collar it may be beneficial to have an outlet so that the water can escape reducing the weight of the riser collar on the manhole. 
     To increase the protection afforded to the outside drop  20 , elbow collar sections  60  can be added to protect the elbow  26  of the outside drop  20  and to support the stack of riser collars  50 ,  150 ,  250  protecting riser  24 . As shown in FIGS. 10 and 11 the elbow collar  60  has a base  68 , which is flat and is placed on the ground next to the base of the manhole  10 . During construction the base of the hole is leveled so that the base  62  of the manhole  10  and the base  68  of elbow collar  60  are at the same level. The elbow collar  60  has an opening  92  to access the boot clamp in boot clamp section  64  for tightening or loosening the boot clam p on the elbow  26  for connecting it to a pipe entering th e manhole  10  at aperture  71 . The elbow collar  60  has a coupler engaging portion  62  and an elbow enclosing portion  66 . The halves of the elbow coupler  60  can be attached to each other by an engagement mechanism  131 . A keyhole shaped aperture  91  and corresponding key can be used to connect the elbow collar  60  to the adjacent elbow collar to surround a pipe. The elbow collar  60  may be filled with sa nd through aperture  82  to make the elbow collar  60  stronger heavier and more protective of elbow  26 . An aperture for allowing water in and out may also be placed on the elbow collar  60 . Tabs  35  having bolt apertures  36  are used to attach the elbow collar  60  to the manhole  10 . Engagement mechanisms  131  are used to secure the halves of the elbow collar  60  together. The engagement mechanism may be bolts though apertures. 
     A T connector  22  is near the top of the manhole which makes it easily accessible and it generally does not need the same kind of protection as the riser  24  and the elbow  26  however a T collar is also possible for the T connector. 
     In an alternative embodiment as shown in FIG. 12 protective risers  350  having the pipe walls  370  on the inside can replace the combination of rises  24  and protective collars  50 ,  150 ,  250  covering the entire length of the riser  24 . The protective rises  350  can come in short length sections  352 , medium length sections  354 , and long length sections  356 . 
     The protective risers  350  are preferably molded as one piece so the inside wall  370  is continuous. The inside wall  370  is protected by the space between the inside wall and the outside of the protective riser to provide a double hull for the fluid flowing in the protective riser  350 . The top and bottom of the protective riser  350  may have pipe like couplings to connect to T couplings, elbows, or other pipes. The protective riser shown in FIG. 13 can come in different lengths as indicated in FIG. 12 with protective risers  352   354  and  356 . The protective rises may have an o-ring  110  in an o-ring groove  115  between sections of protective risers  352 ,  354 ,  356 , or between protective riser  350  and other parts such as a protective elbow  360  with an inside pipe wall  370  as shown in FIG.  14 . As with the split riser collars  50 ,  150 ,  250  and split elbow collars  60  the protective risers  350 ,  352 ,  354 ,  356 , and protective elbows  360  may have apertures  82  for adding sand or apertures  81  for draining water. Further the protective risers  350  and protective elbows  360  can have the same connective means for stacking the sections as the split riser collars  50 ,  150 ,  250  and split elbow collars  60  shown above. The protective risers  350  and protective elbows  360  are also connected to the manholes by bolts through apertures  36  in tabs  35 . 
     At construction sites there may be different sized pipes leading to the manhole  10  at apertures  71  and  73  as shown in FIGS. 15,  16  and  22 . Alternatively the manholes  10  may come with different sized apertures  71  and  73 . In order to efficiently produce and stock only one diameter inside wall  370  for the protective risers  350 ,  352 ,  354 ,  356  for fitting all size manholes  10 , and for all pipe sizes leading to apertures  71 ,  73 , adaptors  400  and  410  are used for the T connectors and adaptors  600  and  610  are used for the elbow connectors. 
     As shown in FIG. 17 an expander T connection adaptor  400  is shown having a wall  401  of a first diameter, and a first angled outer wall portion  402  leading to a wall of a second diameter  403  of a smaller diameter, a second angled outer wall portion  404  leading to a wall of a third diameter  405 . The expander T connection adaptor  400  can be cut at any point long the wall sections  401 ,  403  or  405  to fit the length of the required gap between the riser  24  and the T connector  22 . 
     Similarly a reducer T connection adaptor  410  as shown in FIG. 18 can be used to connect the T connector  22  and the riser  24 . The reducer T connection adaptor  410  has a large diameter wall  411  an angled wall  412  and a second diameter wall  415  for connection to riser. The reducer T connection adaptor  410  may be cut at any position along the walls  411  or  415  to fit the length of the required gap between the riser  24  and the T connector  22 . 
     The pipe connections between sections of pipes may use a collar connector  45  to connect a flange  40  on one pipe to a flange  42  on another pipe. The connector collar  45  has bolts  46  to pull the flanges  40  and  42  into contact as shown in FIG.  19 . 
     Elbow pipe section  600  as shown in FIGS. 20 and 21 may have a reducer  610  or an expander  620  for connecting the elbow section  600  to the manhole  10  at aperture  71 . 
     The elbow pipe  600  may be a pipe in elbow collar  60  or alternatively may be integrally part of the elbow collar  360  as seen in FIG.  12 . In either case a reducer  610  or an expander  620  may be attached to direct the flow of fluids into manhole  10 . In the case of reducer  600  a collar  615  can be used to help align and hold the reducer  600  in place. Alternatively expander  610  a collar  625  can help align and hold the expander  610  in place. 
     In the embodiment shown in FIG. 22 a T connector pipe  22  uses an expander  400  to attach it to the manhole  10  at aperture  71 . A collar connector  45  connects the T connector  22  to expander  400 , which connects to riser  24  having a collar  32  around it to hold the riser  24  to manhole  10 . The riser  24  connects to a pipe  600  having a collar  625  an expander  610  in elbow collar  360 . 
     The connections between pipes and between pipes and between pipes and manholes can be any of the types of connections used in the industry. 
     The collars can be made from polyethylene, polypropylene, fiberglass or any other lightweight strong material. Preferably the collars will be molded for low cost production. 
     Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.