Portable winch

Abstract

A portable winch suitable for use in underground pipe bursting and replacement includes a mounting frame positionable at a top opening of a hole such as a receiving pit or manhole. A telescoping mast having a series of nested, top and bottom mast sections is mounted on the frame. A powered winch unit, also mounted on the frame, includes a drive unit and a cable. A guide assembly includes a sheave that guides the cable from the drive unit to the bottom mast section. Suitable means are connected to the frame for mechanically raising and lowering the mast into and out of the hole. As such, the mast according to the invention does not require assembly or disassembly at the beginning and end of each job. The mechanical means for raising and lowering the mast is preferably the powered winch unit.

1 . A portable winch, comprising: 
 a mounting frame positionable at a top opening of a hole;    a mast including at least upper and lower mast sections;    a swing frame connected by a pivot to the mounting frame and positioned to pivot the mast between a first storage position and a second operating position from which the mast is extendable into the hole;    a power winch mounted on the mounting frame to extend and retract a cable about a sheave connected to the lower mast section; and    a mechanism on the mounting frame that gradually raises and lowers the mast relative to the mounting frame into and out of the hole.    
   
   
       2 . The winch of  claim 1 , wherein the mast sections are telescoping, and the raising and lowering mechanism comprises a second winch positioned for collapsing and extending the telescoping sections.  
   
   
       3 . The winch of  claim 1 , wherein the mechanism for raising and lowering the mast is a power driven mechanism.  
   
   
       4 . The winch of  claim 3 , wherein the mechanism for raising and lowering includes the power winch mounted on the mounting frame and a releaseable connector between the lower mast section and the cable.  
   
   
       5 . The portable winch of  claim 1 , A portable winch, comprising: 
 a mounting frame positionable at a top opening of a hole;    a mast including at least upper and lower mast sections;    a swing frame connected by a pivot to the mounting frame and positioned to pivot the mast between a first storage position and a second operating position from which the mast is extendable into the hole;    a power winch mounted on the mounting frame to extend and retract a cable about a sheave connected to the lower mast section; and    a mechanism on the mounting frame that gradually raises and lowers the mast relative to the mounting frame into and out of the hole, wherein the upper mast section is slidably mounted on the swing frame, the winch further comprising a latch for securing the upper mast section in the swing frame at one of a plurality of predetermined locations.    
   
   
       6 . The portable winch of  claim 5 , wherein the upper mast comprises a series of holes wherein the latch may be selectively engaged and a reinforcing strip for reinforcing the mast around one or more of the holes.  
   
   
       7 . The portable winch of  claim 1 , wherein the mounting frame comprises a wheeled trailer having a plurality of extendable jacks for supporting the mounting frame.  
   
   
       8 . The portable winch of  claim 1 , further comprising a powered pivoting mechanism configured to swing the mast and swing frame about the pivot between the storage position and the operating position.  
   
   
       9 . The portable winch of  claim 8 , wherein the powered pivot mechanism comprises a hydraulic cylinder having one end secured to the mounting frame and the other end secured to the swing frame.  
   
   
       10 . A method for deploying a portable winch comprising a mounting frame, a mast including at least two top and bottom mast sections, which mast is mounted to the mounting frame by a pivot mechanism, and a power winch mounted on the mounting frame to extend and retract a cable about a sheave connected to the bottom mast section, comprising: 
 positioning the mounting frame of the portable winch at a top opening of a hole;    pivoting the mast by the pivot mechanism from a horizontal position to a vertical position;    lowering the mast into the hole;    securing the mast in the hole for horizontal pulling using a pulling cable wound over a sheave;    after use of the power winch, unsecuring the mast so that the mast can be removed from the hole; and    raising the mast from the hole by operating a mechanical mast control system that gradually pulls the lower mast section upwardly relative to the mounting frame.    
   
   
       11 . The method of  claim 10 , further comprising, after raising the mast from the hole, pivoting the mast sections from a vertical position to a horizontal position using the pivot mechanism.  
   
   
       12 . The method of  claim 10 , wherein the mast control system comprises a second winch mounted on the mounting frame.  
   
   
       13 . The method of  claim 10 , wherein the mast comprises telescoping sections that are extended and retracted by the mast control system.  
   
   
       14 . The method of  claim 10 , wherein the mast control system is power-driven.  
   
   
       15 . The method of  claim 14 , wherein the mast control system includes the power winch mounted on the mounting frame and a releaseable connector between the lower mast section and the cable.  
   
   
       16 . The method of  claim 10 , wherein lowering the mast into the hole comprises operating the mechanical mast control system to gradually lower the bottom mast section.  
   
   
       17 . The method of  claim 10 , wherein pivoting the mast from a horizontal position to a vertical position is carried out using a powered pivot mechanism.