Patent Publication Number: US-4650232-A

Title: Manhole cover lifter

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The device of this invention resides in the area of manhole cover lifters and more particularly relates to an improved manhole cover lifter having means to clean out and gain access into manhole cover rim notches and means to lift and move said manhole cover out of the manhole frame without having to manually lift the manhole cover. 
     2. Description of the Prior Art 
     Manhole covers, although particularly well known with regard to sewer systems, are also used in many different types of in-ground installations. To gain access to a manhole in the ground, one must first lift and remove the manhole cover therefrom. Manhole covers are heavy and often can weigh in excess of 180 lbs. The standard practice in the prior art has been to jam a crowbar into a notch located at the rim of the manhole cover, pry the cover up and then manually lift it out. This procedure frequently causes problems in that the manhole cover is extremely heavy and persons lifting out the cover can strain muscles trying to pry it up and lift it out. Moreover, the notch(es) around the cover&#39;s perimeter can be filled with tar and other debris which the compaction thereof can prevent easy insertion of the pry bar. Further, the manhole cover, when lifted out, can fall on the worker&#39;s hands and feet causing serious injury. 
     A body of art has developed which includes the following U.S. patents: 
     U.S. Pat. No. 3,275,299 Meshew 
     U.S. Pat. No. 3,985,338 Herrmann 
     U.S. Pat. No. 4,365,925 Girtz 
     U.S. Pat. No. 4,482,182 Mortensen 
     Some of the prior art devices disclosed in the above-mentioned patents have means to latch onto holes defined within the manhole cover, either at a side or at a center point thereof and to lock thereon so that the device and cover can be rotated on a pivot member of the device, and the cover lifted out. One problem with some of the above-mentioned prior art is that some manhole covers in current use do not have such holes extending all the way therethrough. Many manhole covers today have a receipt notch in one or more positions around their perimeter, and it is this notch which is felt most practical to address because it is so commonly used. One device that does address the lifting of this type of manhole is disclosed in U.S. Pat. No. 4,482,182 to Mortensen listed above. The device as disclosed has means to latch into opposing notches on each side of the cover by means of a complex mechanism so that such cover can be lifted out by the use of such tool. A problem with prior art tools is that often due to the complexity of the tool and/or tightly sealed-in covers such tools are difficult to use. 
     SUMMARY OF THE INVENTION 
     It has long been felt desirable to develop a safe and easy-to-use manhole cover lifter. Therefore it is an object of this invention to provide a non-complex, simplified tool which can be utilized by an individual with the currently existing sytle of receipt notched manhole covers. 
     It is a further object to remove such manhole cover without the necessity of an individual manually touching or handling the cover. 
     It is yet a still further object of this invention to remove such covers with ease even if the receipt notches in the cover are plugged with tar or debris. 
     The body of the tool disclosed herein terminates with a tip member which is curved and is adapted to be inserted into a receipt notch in the manhole cover. A handle positioned perpendicular to the body allows the user to first manipulate the tool to insert the tip into the notch. One then rotates the handle back and forth which movement twists the curved tip member which action drives it into the receipt notch, clearing away any debris or tar from the receipt notch so that the tip can be inserted further therein. One then pulls back on the handle, lifting the cover upwards and somewhat out of the manhole frame. A shovel or other bar-like implement can then be inserted under the cover to hold it up, and the tool removed from the notch. The tool is then rotated 90 degrees sideways and pushed under the cover and once under the cover, the tool is rotated back again to its original position wherein a tooth formed on the end of the tool extends upward under and engages into the reinforcement braces which are found under most manhole covers. The tool is pulled backwards by the handle with the tooth pulling the manhole cover out of the frame. The device of this invention then can be rested on the ground with the handle acting as a stabilizer which handle prevents the device from rotating and falling over. One can leave the manhole cover resting on the tool of this invention if desired. To return the cover, one merely lifts the upper handle on the curved portion of the tool and slides the cover on the tool back toward and then into the manhole frame again into a position where the manhole cover is seated on the cover seat rim of the manhole frame. One then twists the tool 90 degrees, disengaging the tooth from the cover&#39;s reinforcement brace&#39;s and pulls the tool out from under the manhole cover which stays in position and falls the short remaining distance onto its seat. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates a side view of the tool of this invention. 
     FIG. 2 illustrates a front view of the tool of this invention. 
     FIG. 3 illustrates the tool of this invention in use cleaning out a notch in a manhole cover. 
     FIG. 4 illustrates a cutaway view of the tool in the manhole cover&#39;s notch. 
     FIG. 5 illustrates the tool being inserted under a manhole cover. 
     FIG. 6 illustrates the tool being rotated so that its tooth engages the manhole cover&#39;s reinforcement brace(s). 
     FIG. 7 illustrates a manhole cover resting on the tool of this invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
     FIG. 1 illustrates a side view of the tool of this invention which shows the body 22 and the end of first handle 12 perpendicular thereto. The tool is seen in greater detail in FIG. 2 which is a front view positioned 90 degrees to the view shown in FIG. 1. The second handle 16 seen on top of the tool where body 22 curves from the position of handle 12 and extends as handle portion 14 which can be reinforced by brace 18 if needed. At the bottom of the tool is tooth 26 and curved tip 24 which is used to engage manhole cover notch 28 as seen in FIG. 3. 
     In FIG. 3 a user is shown rotating the tool by handle 12 causing curved tip 24 to clear debris out of notch 28 of manhole cover 30. Once the notch is cleaned out as seen in FIG. 4, one inserts the curved tip into notch 28 of the cover and pries upwards using the rear of the tool touching the rim and/or the ground as a fulcrum. When the cover is lifted away from the frame, one inserts a shovel or other suitable tool 25 under the cover to hold a side of the cover clear of the frame with a space therebetween. One then rotates the tool 90 degrees as seen in FIG. 5 and pushes it under the manhole cover. One then rotates the tool back to its original position having tooth 26 as seen in FIG. 6 engage upwards against reinforcement brace 32 of manhole cover 30. The manhole cover is then pulled out of manhole 35 as seen in FIG. 7, and the tool can then be rested on the ground. The tool will not fall over and will maintain its position because handle 12 is then used as a stand to hold the tool upright. Most current manhole covers have braces underneath of one type or another against which the tooth can engage. Although the configuration of the braces may differ from manhole to manhole, there is always some underlying cover structure which tooth 26 can latch onto when the tool is pulled or pushed moving the cover back into its original position. Once the cover is returned onto the manhole frame by pushing it while it rests on the tool, the tool is rotated 90 degrees, disengaging the tooth from the reinforcement braces of the cover and is slid out from under the cover. The cover then falls the remaining short distance onto its seat. 
     Although the present invention has been described with reference to particular embodiments, it will be apparent to those skilled in the art that variations and modifications can be substituted therefor without departing from the principles and spirit of the invention.