Magnetic cover remover

Abstract

A cover removal apparatus in embodiments of the invention may include one or more of the following features: (a) a frame, (b) an electromagnet, (c) a power source electrically coupled to the electromagnet for selectively energizing the electromagnet, (d) means for positioning the electromagnet relative to a cover, the means for positioning coupled to the frame and to the electromagnet, (e) means for loosening the cover, and (f) a hydraulic actuator that forces the second hydraulic ram and the hammer toward the cover to apply a loosening force to the cover with the hammer device.

1 . A cover removal apparatus, comprising:
 a frame;   an electromagnet;   a power source electrically coupled to the electromagnet for selectively energizing the electromagnet;   means for positioning the electromagnet relative to a cover, the means for positioning coupled to the frame and to the electromagnet; and   means for loosening the cover.   
   
   
       2 . The apparatus of  claim 1 , wherein the means for positioning includes a first hydraulic ram coupled to the electromagnet at a distal end of the hydraulic ram. 
   
   
       3 . The apparatus of  claim 1 , wherein the electromagnet is adapted to magnetically attach to the cover when the electromagnet is energized. 
   
   
       4 . The apparatus of  claim 1 , wherein the means for loosening the cover includes a second hydraulic ram having a hammer coupled to the distal end of the second hydraulic ram. 
   
   
       5 . The apparatus of  claim 4 , further including a hydraulic actuator that forces the second hydraulic ram and the hammer toward the cover to apply a loosening force to the cover with the hammer device. 
   
   
       6 . The apparatus of  claim 2 , wherein the means for loosening the cover is a spring hammer apparatus comprising:
 a second electromagnet electrically coupled to the power source;   a first steel plate capable of electromagnetically coupling to the second magnet;   a second steel plate;   a spring coupled to the first plate at a first end and the second plate at a second end;   a rod extending through the second plate; and   a hammer device coupled to the first plate at one end and the rod at the opposite end.   
   
   
       7 . The apparatus of  claim 6 , further comprising a connecting pin coupled to the first electromagnet at one end and slideably received by the second plate at an opposite end, wherein the spring is expanded when the first electromagnet is lowered adjacent the cover. 
   
   
       8 . The apparatus of  claim 7 , wherein the rod contacts the cover to loosen the cover from a cover casting when the second magnet is deenergized causing the spring to contract transferring the contraction force to the rod. 
   
   
       9 . The apparatus of  claim 1 , wherein the means for loosening the cover is fixedly attached to the frame. 
   
   
       10 . The apparatus of  claim 1 , wherein the frame is attachable to a vehicle for transporting and positioning the cover removal apparatus. 
   
   
       11 . A cover removal apparatus, comprising:
 a frame;   an electromagnet;   a power source electrically coupled to the electromagnet for selectively energizing the electromagnet;   means for positioning the electromagnet relative to a cover, the means for positioning coupled to the frame and to the electromagnet; and   a support assembly for the frame comprising:
 a ratcheted support stem selectively positionable relative to the frame; 
 a ground support coupled to the support stem at a first end; and 
 a handle coupled to the support stem at a second end. 
   
   
   
       12 . The apparatus of  claim 11 , further comprising a release tab supported by the frame, the release tab selectively restricting movement between the support stem and the frame. 
   
   
       13 . The apparatus of  claim 12 , wherein the ground support and support stem are permitted to drop toward a ground surface when the release tab is lifted. 
   
   
       14 . The apparatus of  claim 13 , wherein the ground support can be lifted from the ground surface and positionable relative to the frame when an operator pulls up on the handle of the support stem. 
   
   
       15 . The apparatus of  claim 13 , wherein the ground support is a swivel wheel allowing the support assembly to travel with the cover removal apparatus. 
   
   
       16 . A method for removing a manhole cover, comprising:
 positioning an electromagnet overtop of a manhole cover;   lowering the electromagnet onto the cover;   energizing the electromagnet with a power source;   loosening the cover with a cover loosening device adjacent to the electromagnet;   lifting the electromagnet with the cover.   
   
   
       17 . The method of  claim 16 , further comprising the step of removing the manhole cover from overtop of a manhole cover casting. 
   
   
       18 . The method of  claim 17 , further comprising the step of lowering the electromagnet and cover a distance from the manhole cover casting and deenergizing the electromagnet. 
   
   
       19 . The method of  claim 16 , wherein the cover loosening device is a hammer device actuated by a hydraulic ram. 
   
   
       20 . The method of  claim 16 , wherein the cover loosening device is a spring actuated hammer device. 
   
   
       21 . The method of  claim 16 , further comprising the step of releasing a ratcheted support stem having a wheel at one end a ground surface and locking the ratcheted support stem in place with a release tab. 
   
   
       22 . The method of  claim 21 , further comprising the step of pulling a handle connected to an opposite end of the ratcheted support stem to lift the wheel off of the ground surface.