Abstract:
A pipe shut off tool is provided which may comprise a jaw that may be engaged to a defective pipe and a pump operative to translate the jaw between a crimping position and a release position. The jaw and pump may be connected to each other via an elongate flexible hose such that the jaw may inserted into a compact space and engage the pipe located therein and the pump may be placed outside of the compact space near the operator such that the tool operator may translate the jaw to the crimping position from outside the compact space.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not Applicable 
   STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
   Not Applicable 
   BACKGROUND OF THE INVENTION 
   The present invention relates generally to a pipe shut off tool for cutting off fluid flow through a pipe, and more particularly, to a hydraulically operated pipe shut off tool. 
   Prior art pipe shut off tools generally have two plates which may be tightened or compressed onto a pipe to prevent fluid flow through the pipe. One method of tightening or compressing the plates onto the pipe is via a set of bolts. For example, two plates may be adjacently aligned to each other and bolted together with four bolts, one bolt located at each of four corners of the plates. The pipe may be placed between the plates with two bolts on each side of the pipe. Thereafter, the bolts may be tightened so as to draw the two plates together onto the pipe until the pipe has been crimped to prevent fluid flow through the pipe. However, tightening the bolts is a time consuming process because all four bolts must be tightened simultaneously and tightening the bolts may be a slow process, especially when tightened via a hand held wrench—manual wrench. 
   Further, the process of tightening the bolts may be cumbersome because the pipe to be shut off (i.e., the subject pipe) may be confined in a compact space such that the tool operator cannot reach the bolts with the wrench to tighten the bolts. For example, a building may have a system of pipes which supply water to the building&#39;s restrooms, sinks, and water fountains. Some of the pipes may be piped between walls, within compact spaces, and adjacent other structures (e.g., cement or metal pillars). If one of these pipes leaks or bursts, then surrounding drywall or other structures may have to be removed such that maintenance personnel can shut off the water flowing through the pipe. However, certain structures within the building may not be removable such as load bearing columns, metal or cement structures. Accordingly, such structures may interfere with maintenance personnel&#39;s ability to position the pipe shut off tool over the broken pipe and tighten the bolts. 
   Accordingly, there is a need in the art for an improved pipe shut off tool. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention alleviates the above-identified and other deficiencies in the prior art. The pipe shut off tool of the present invention may comprise a pump, a hose, a cylinder and a jaw which may be hydraulically and mechanically connected to each other. The pump may be hydraulically connected to the cylinder via the hose. Also, the cylinder may be mechanically connected to the jaw. The hose may be an elongate flexible hose such that the jaw may be placed around the pipe which may be located in a compact space, and the pump may be placed near the tool operator (e.g., maintenance personnel) away from the compact space. This allows the operator to conveniently operate the jaw from outside the compact space. 
   The pump may be a hand pump having a handle. The handle may be strokable between first and second positions. The handle is in the first position when the handle is parallel with a body of the pump and in the second position when the handle is oblique with the pump body. Each stroke (i.e., first position to second position and back to the first position) of the hand pump handle may displace hydraulic fluid from the pump body through the hose and toward the cylinder. The cylinder may be attached to the jaw such that first and second crimping surfaces of the jaw may be drawn toward each other during each handle stroke. If a pipe is placed between the first and second crimping surfaces, then the crimping surfaces may crimp the pipe to prevent fluid flow through the pipe by repeatedly stroking the handle. This combination of pump, elongate flexible hose, cylinder and jaw provides a convenient method of crimping the pipe by locating the mechanism (i.e., pump) which actuates the jaw away from the jaw itself via the flexible elongate hose. For example, the jaw may be placed within the compact space and actuated by the pump outside of the compact space. Hence, operation of the pipe shut off tool is convenient. 
   The pipe shut off tool is also advantageous for use in shutting off fluid flow through an underground pipe. For example, dirt surrounding a leaking underground pipe may be removed to expose the leaking underground pipe such that maintenance personnel may fix the leaking underground pipe. However, since the leaking underground pipe is below ground level, the maintenance personnel may place the jaw around the leaking underground pipe and place the pump at ground level to conveniently operate the jaw around the underground pipe until fluid flow through underground pipe is shut off. 
   The pump may also be a two speed pump. The pump may operate at a first speed prior to the first and second crimping surfaces applying crimping pressure onto the pipe. After a threshold crimping pressure is applied to the pipe or hydraulic fluid of the pump reaches a threshold pressure, then the pump may operate at a second speed. The first speed pumps hydraulic fluid from the pump at a greater rate than the second speed and draws the crimping surfaces together at a faster rate than the second speed. In other words, the crimping surfaces may be rapidly closed onto the pipe until the crimping surfaces contact the pipe and the hydraulic fluid threshold pressure is reached. Thereafter, the pump may transition to the second speed. During the second speed, the jaw closes onto the pipe at a slower rate than during the first speed but is capable of applying greater pressure or force onto the pipe compared to the pressure or force applyable to the pipe during the first speed. This arrangement provides for rapid travel of the crimping surfaces onto the pipe and higher application pressure once the crimping surfaces contact the pipe. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An illustrated and presently preferred embodiment of the present invention is shown in the accompanying drawings in which: 
       FIG. 1  is a perspective view of a jaw, a cylinder, an elongate flexible hose and a pump wherein the jaw and the cylinder are mechanically connected to each other and the cylinder, the elongate flexible hose and the pump are hydraulically connected to each other; 
       FIG. 2A  is a perspective view of a pipe between crimping surfaces of the jaw prior to the crimping surfaces applying crimping pressure onto the pipe; 
       FIG. 2B  is a perspective view of the pipe between crimping surfaces of the jaw when the crimping surfaces begin to apply crimping pressure onto the pipe; 
       FIG. 2C  is a perspective view of the pipe between crimping surfaces of the jaw when fluid flow through the pipe is shut off; 
       FIG. 3  is a cross sectional view of the jaw, the cylinder and the pipe of  FIG. 2A ; 
       FIG. 4  is a cross sectional view of the jaw, the cylinder and the pipe of  FIG. 2C ; 
       FIG. 5  is an exploded cross sectional view of the jaw and the cylinder of  FIGS. 3 and 4 ; 
       FIG. 6  is a side view of a saddle and a post; 
       FIG. 7  is a front view of  FIG. 6 ; and 
       FIG. 8  is a perspective view of a right side wall of the jaw of  FIG. 5 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The figures referred to herein are for the purpose of illustrating the preferred embodiments of the present invention and not for the purpose of limiting the same.  FIG. 1  illustrates a pipe shut off tool  10  comprising a pump  12 , a hose  14 , a cylinder  16  and a jaw  18 . The pump  12  shown in  FIG. 1  is a manual pump (e.g., hydraulic hand pump) but it is also contemplated within the scope of the present invention that the pump  12  may be an automatic pump. By way of example and not limitation, the various aspects of the present invention discussed herein will be discussed in relation to the hydraulic hand pump. 
   The pump  12  may be a single speed pump or a two speed pump such as those manufactured by ENERPAC. A single speed pump displaces an equal amount of hydraulic fluid through a hydraulic fluid output  20  during each stroke (defined below) of a handle  22  of the pump  12  despite an increase in pressure of the pump hydraulic fluid. A two speed pump displaces a variable amount of hydraulic fluid through the hydraulic fluid output  20  of the pump  12  based on the hydraulic fluid pressure. In particular, more hydraulic fluid is displaced through the hydraulic fluid output  20  when the hydraulic fluid pressure is below a threshold pressure compared to the amount of hydraulic fluid displaced through the hydraulic fluid output  20  when the hydraulic fluid pressure is above the threshold pressure. 
   The pump handle  22  may be traversable between a first position (see  FIG. 1 ) and a second position. The handle  22  is in the first position when the handle  22  is parallel to a body  24  of the pump  12  and is in the second position when the handle  22  is oblique to the pump body  24 . Hydraulic fluid contained within the pump body  24  may be made ready for pumping by traversing the handle  22  from the first position to the second position. As the handle  22  is subsequently traversed from the second position to the first position, hydraulic fluid may be displaced through the hydraulic fluid output  20  into the hose  14  and toward the cylinder  16 . The traversal of the handle  22  from the first position to the second position and back to the first position is one stroke of the handle  22 . 
   The pump  12  may be attached to the cylinder  16  and be in hydraulic communication therewith via the hose  14 . The hose  14  may be a flexible elongate steel-reinforced rubber hose about six (6) feet long. The elongate hose  14  allows maintenance personnel to place the jaw  18  around a leaking pipe  26  (see  FIG. 2A ) and the pump  12  (see  FIG. 1 ) away from the leaking pipe  26 , near the tool operator. For example, if an underground pipe  26  was leaking, then the jaw  18  may be placed around the underground pipe  26  and the pump  12  may be placed on the ground such that the tool operator may conveniently operate the jaw  18  by stroking the pump handle  22  at ground level without having to bend down into a dirt hole, near the jaw  18  and pipe  26 , to operate the jaw  18 .  FIGS. 2B and 2C  illustrate operation of the jaw  18  as it crimps the pipe  26  to prevent fluid from flowing therethrough. 
   Referring now to  FIGS. 3–5 , the cylinder  16  (see  FIG. 1 ) may comprise a housing  30 , a plunger  32  and a spring  34 . The spring  34  may be an extension spring attached to the plunger  32  and the housing  30  to maintain the plunger  32  in a retracted position (see  FIG. 3 ) and translate the plunger  32  from an extended position (see  FIG. 4 ) to the retracted position. In particular, the spring  34  may define a cylindrical distal end  36  (see  FIG. 5 ) and a conical distal end  38  (see  FIG. 5 ). The cylindrical distal end  36  may further have a hook  40  (see  FIG. 5 ) which may engage a mating screw  42  (see  FIGS. 3–5 ) fixedly engaged to an inner surface  44  (see  FIG. 5 ) of the cylinder  16 . The conical distal end  38  may engage a bushing  46  (see  FIGS. 3–5 ) connected to a distal portion  48  (see  FIG. 5 ) of the plunger  32 . A screw  50  (see  FIG. 5 ) may be inserted into the bushing  46  (see  FIGS. 4 and 5 ) and locked to the plunger distal portion  48  via an acorn nut  52  (see  FIGS. 3–5 ). 
   The plunger  32  may be translated to the extended position by stroking the pump handle  22 . During each stroke of the pump handle  22 , hydraulic fluid may be pumped out of the pump  12  into the hose  14  and toward and into a cavity  54  (see  FIGS. 4 and 5 ) of the cylinder  16 . As more fluid is displaced into the cylinder cavity  54 , the plunger  32  may be traversed to the extended position against a spring force of the spring  34  and a deformation force required to crimp the pipe  26 . After the plunger  32  is traversed to the extended position and the leaking pipe  26  fixed, a release valve  56  (see  FIG. 1 ) on the pump  12  may be opened to displace the hydraulic fluid pumped into the cylinder cavity  54  back into the pump  12  via the spring force. In other words, when the release valve  56  is closed, pumping action of the handle  22  displaces hydraulic fluid through the hydraulic fluid output  20  into the cylinder  16 . Conversely, when the release valve  56  is opened, hydraulic fluid pumped into the cylinder  16  is displaced back into the pump body  24 . 
   The cylinder  16  may be attached to the jaw  18 . The housing  30  may have a housing distal portion  58  (see  FIG. 5 ) and the plunger  32  may have the plunger distal portion  48 . The housing distal portion  58  may be externally threaded  60  and the plunger distal portion  48  may be internally threaded  62 . The jaw  18  may have a body  64  (see  FIG. 5 ) attached to the housing  30  and a crimping member  66  may be attached to the plunger  32  (see  FIGS. 3–5 ). The jaw body  64  and the crimping member  66  may define first and second surfaces  68 ,  70  (see  FIGS. 3 and 5 ), respectively which may be drawn together with each stroke of the handle  22 . 
   The jaw body  64  may have a support portion  72  and a crimping portion  74  (see  FIG. 5 ). The support portion  72  may have an aperture  76 . The aperture  76  may have a cylindrical configuration and be internally threaded  78 . The aperture internal threads  78  may be threadably engagable to the housing distal portion external threads  60 . The aperture  76  may also define a plunger axis  80  in that the plunger  32  is traversed between the retracted position (see  FIG. 3 ) and the extended position (see  FIG. 4 ) along the plunger axis  80 . 
   The crimping member  66  may comprise a post  82  and saddle  84  (see  FIG. 5 ). The post  82  may be rotateably attached to the saddle  84  about a pivot point  86 . The post  82  may have two tines  88   a, b  (see  FIG. 6 ) and the saddle  84  may fit between the two tines  88   a ,  88   b . The saddle  84  may have a circular aperture  90  which corresponds to apertures  92   a, b  formed on the tines  88   a, b . The saddle aperture  90  and the tine apertures  92   a, b  may be aligned and a pin  94  (see  FIG. 7 ) may plug the apertures  90 ,  92   a ,  92   b . The pin  94  may have a friction fit with the tine apertures  92   a, b  and a loose fit with the saddle aperture  90  such that the saddle  84  may rotate about the pin  94 . The tines  88   a, b  may be attached to a base  96  (see  FIG. 6 ). The base  96  may define an inner surface  98  (see  FIG. 6 ) which may contact a surface  100  (see  FIGS. 3–6 ) of the saddle  84  to prevent the saddle  84  from excessively rotating about the pin  94 . The post  82  may have external threads  102  formed on its base  94  which are threadably engagable to the plunger distal portion internal threads  62  (see  FIG. 5 ). Accordingly, as the cylinder  16  is traversed between the retracted position (see  FIG. 3 ) and the extended position (see  FIG. 4 ), the crimping member  66  (see  FIGS. 3 and 4 ) may be respectively traversed between a release position (see  FIGS. 2A and 3 ) and a crimping position (see  FIGS. 2C and 4 ). Further, as shown in  FIG. 3 , the apertures  90 ,  92   a ,  92   b  may be aligned with the plunger axis  80 . 
   The jaw body  64  (see  FIGS. 1 ,  5  and  8 ) may include left and right sidewalls  104   a, b  placed adjacently parallel to each other. The left and right sidewalls  104   a, b  may be a mirror configuration with respect to each other. Left and right guides  106   a, b  (see  FIGS. 1 ,  5 , and  8 ) may also be attached to inner surfaces  108  (see  FIG. 8 ) of the left and right sidewalls  104   a, b . These guides  106   a, b  abut the saddle  84  (see  FIGS. 3 and 4 ) and maintain the saddle  84  in a perpendicular relationship with the pipe  26  inserted into the jaw  18  along the entire traversal distance (i.e., between release position and crimping position; see  FIGS. 2A–2C ) of the saddle  84 . In other words, the guides  104   a, b  prevent the saddle  84  from rotating about the plunger axis  80 . 
   The left and right sidewalls  104   a, b  may have a support filler  110  (see  2 A,  5  and  8 ) interposed therebetween. The support filler  110  may define the internally threaded apertures  78  (see  FIGS. 5 and 8 ) threadably engageable to the housing distal portion external threads  60 . The left and right sidewalls  104   a, b  may also have a crimping filler  112  (see  FIGS. 2A and 8 ) interposed therebetween. The crimping filler  112 , left side wall  104   a  and right side wall  104   b  may define the first crimping surface  68 . The first crimping surface  68  may be substantially flat and/or pitted to receive an exterior surface  114  of the pipe  26 . Also, the second crimping surface  70  may be substantially flat and/or pitted to receive the pipe exterior surface  68 . The first crimping surface  68  may also be perpendicular to the plunger axis  80 . Also, the first and second crimping surfaces  68 ,  70  may be parallel to each other. 
   The support portion  72  (see  FIG. 5 ) may also define an oblique surface  116  (see  FIG. 5 ) with respect to the first and second crimping surfaces  68 ,  70 . The oblique surface  116  may be pitted or flat. The oblique surface  116  and the first crimping surface  68  may have a “V” shaped configuration (see  FIG. 5 ), and the pipe  26  may be inserted between the first and second crimping surfaces  68 ,  70  (see  FIG. 2A ) until the pipe exterior surface  114  physically contacts the oblique surface  116 . The oblique surface  116  may maintain a status quo relationship between a central axis  118  of the pipe  26  and the plunger axis  80 . For example, if the plunger axis  80  is under-center, as shown in  FIG. 3 , with respect to the central axis  118  (see  FIG. 3 ) of the pipe  26  inserted between the first and second crimping surfaces  68 ,  70 , then the oblique surface  116  maintains the under-center relationship despite changes in a diameter of the inserted pipe  26 . If the pipe diameter is too small then the plunger axis  80  may become over-center with respect to the pipe central axis  118  but for large pipe diameters, the oblique surface  116  urges the plunger axis  80  into the under-center relationship with the pipe central axis  118 . Alternatively, if the plunger axis  80  is substantially aligned to the pipe central axis  118 , then the oblique surface  116  maintains the substantial alignment between the pipe central axis  80  and the plunger axis  118  except for excessively large or small pipe diameters. It is also contemplated within the scope of the present invention that if the plunger axis  80  is over-center with respect to the pipe central axis  118  (preventing the pipe  26  from slipping out of the jaw  18  as the crimping member  66  is traversed from the release position to the crimping position), then the oblique surface  116  prevents the pipe central axis  80  from becoming too over-center such that excessive torque is not applied to the plunger  32 . 
   To use the tool  10 , the user may open the pump release valve  56  to ensure that the cylinder  16  is in the retracted position. The pipe  26  may be inserted into the jaw  18  between the first and second crimping surfaces  68 ,  70  (see  FIG. 2A ). The pump handle  22  may be repetitively stroked to pump hydraulic fluid from the pump body  24  into the cylinder  16 . During this initial stage before the crimping member  66  applies any appreciable pressure or force on the pipe  26 , the pump  12  may displace hydraulic fluid out through the hydraulic fluid output  20  at a high rate (i.e., first speed): the first and second crimping surfaces  68 ,  70  closes onto the pipe  26  at a high rate. As the handle  22  is further stroked, the crimping member  66  may physically contact the pipe  26  and increase pressure of the pump hydraulic fluid. Once the pressure of the hydraulic fluid increases above a threshold pressure (e.g., about 200 psi) which means that an appreciable pressure is applied on the pipe  26  by the crimping member  66 , the pump  12  transitions to the second speed. The second speed displaces hydraulic fluid through the hydraulic fluid output  20  at a rate less than the first speed. However, the hydraulic fluid may reach pressures of up to about 10,000 psi, and as a result, more pressure may be applied to the pipe  26  during the second speed compared to the pressure applyable to the pipe  26  during the first speed by the crimping member  66 . This allows the user to quickly traverse the crimping member  66  to the crimping position from the release position until the crimping member  66  contacts the pipe  26 . Once the crimping member  66  contacts the pipe  26 , more pressure is required to squeeze the pipe  26  shut. As such, the pump  12  may automatically or manually transition to the second speed—higher pressure (e.g., about 10,000 psi hydraulic fluid pressure) but slower rate of fluid transfer. In tests, a two inch copper pipe was crimped shut in less than ten (10) seconds. 
   This description of the various embodiments of the present invention is presented to illustrate the preferred embodiments of the present invention, and other inventive concepts may be otherwise variously embodied and employed. The appended claims are intended to be construed to include such variations except insofar as limited by the prior art.