Shutoff tool for plastic pipe

Claim 2

A pipe shutoff tool, operable from above the surface of the ground for squeezing closed a section of plastic pipe in a pipeline located below ground level, said tool comprising: a handle assembly; a clamp head operatively coupled to one end of said handle assembly; a first guide rod rigidly mounted at one end through one side of said clamp head, and having a locking device formed on the other end; a second guide rod slidably and rotatably mounted through the opposite side of said clamp head parallel to said first guide rod; a first die member slidably engaged on and slidably mounted between said first and second guide rods; a second die member nonrotatably mounted to said second guide rod and adapted for releasably engaging said locking device on the other end of said first guide rod in a first position, and adapted for rotating to a second position; means operable from the other end of said handle assembly and coupled to Said clamp head and to said first die member for urging said die members together with sufficient force to collapse and close a section of plastic pipe disposed between said die members when said second die member is in said first position; means coupled to said second guide rod and operable from the other end of said handle assembly for disengaging said second die member from said locking device and for rotating said second die member between said first and second positions.

Claim 3

The shutoff tool of claim 1 wherein said locking device includes a nut having a protruding annular shoulder; and said second die member has a slotted face adapted for engaging said first guide rod and a recess formed around said slotted face adapted for releasably engaging said shoulder.

Claim 4

A pipe shutoff tool, operable from above the surface of the ground for squeezing closed a section of plastic pipe to temporarily shut off the flow of fluid or gas in a pipeline located below ground level, said tool comprising: a hand assembly; a header coupled to one end of said handle assembly; a pair of laterally spaced, parallel guide rods, a first said guide rod being rigidly mounted at one end to said header, a second said guide rod slidably and rotatably received in said header, said header extending between said guide rods, the other end of said first guide rod having a locking head thereon; an elongated first die member slidably engaged on and extending between said guide rods, said first die member having a first elongated pipe closure die surface; an elongated second die member rigidly mounted to said second guide rod and releasably engageable with said locking head on the other end of said first guide rod and adapted for extending between said guide rods, said second die member having a second elongated pipe closure die surface; jack means carried by said header and coupled with said first die member and operable to shift said first die member into and out of engagement with said second die member, said jack means being operable from the other end of said handle assembly; and a control linkage extending from the other end of said handle assembly to said second guide rod and adapted to disengage said second die member from said locking head and rotate said second die member out of and into engaging alignment with said first die member, said control linkage being operable from the other end of said handle assembly.

Claim 5

A pipe shutoff tool, operable from above the surface of the ground for squeezing closed a section of plastic pipe to temporarily shut off the flow of fluid or gas in a pipeline located below ground level, said tool comprising: a hand assembly; a header coupled to one end of said handle assembly; a pair of laterally spaced, parallel guide rods, a first said guide rod being rigidly mounted at one end to said header, a second said guide rod slidably and rotatably received in said header, said header extending between said guide rods, the other end of said first guide rod having a locking head thereon; an elongated first die member slidably engaged on and extending between said guide rods, said first die member having a first elongated pipe closure die surface; an elongated second die member rigidly mounted to said second guide rod and releasably engageable with said locking head on the other end of said first guide rod and adapted for extending between said guide rods, said second die member having a second elongated pipe closure die surface; jack means carried by said header and coupled with said first die member and operable to shift said first die member into and out of engagement with said second die member, said jack means being operable from the other end of said handle assembly; and a control linkage extending from the other end of said handle assembly to said second guide rod and adapted to disengage said second die member from said locking head and rotate said second die member out of and into engaging alignment with said first die member, said control linkage being operable from the other end of said handle assembly.

Claim 6

The shutoff tool of claim 3 further comprising separate spring devices mounted on the front and rear surfaces of said first die member, each of said separate spring devices having first and second end sections crossing substantially at the lateral center of said first elongated pipe closure die surface, each said end section terminating in an arcuate loop extending below the first pipe closure die surface in the absence of pressure applied thereto, said first and second end sections defining a concave cradle adapted for receiving the pipe therein.

Claim 7

A self-aligning shutoff tool for squeezing closed a resilient, deformable pipe, said tool comprising: opposed die members movably mounted on said tool and adapted to receive and squeeze said pipe therebetween; means for urging said die members together; and resilient means for axially and laterally aligning said tool on said pipe; said resilient means including a plurality of separate resilient means spaced apart from and independent of one another; each of said separate resilient means comprising a spring having first and second end sections crossing substantially on the centerline of said die members parallel to the direction of movement of said die members, said end sections forming a cradle centered at the point of crossing and adapted for receiving said pipe therein; whereby said tool is axially and laterally centered on said pipe in response to forces produced by said first and second end sections.

Claim 8

A self-aligning shutoff tool for squeezing closed a resilient, deformable pipe, said tool comprising: opposed die members movably mounted on said tool and adapted to receive and squeeze said pipe therebetween; means for urging said die members together; and resilient means for axially and laterally aligning said tool on said pipe; said resilient means including a plurality of separate resilient means spaced apart from and independent of one another; each of said separate resilient means comprising a spring having first and second end sections crossing substantially on the centerline of said die members parallel to the direction of movement of said die members, said end sections forming a cradle centered at the point of crossing and adapted for receiving said pipe therein; whereby said tool is axially and laterally centered on said pipe in response to forces produced by said first and second end sections.

Claim 9

A self-aligning shutoff tool for squeezinG closed a section of plastic pipe to temporarily shut off the flow of fluid or gas in a pipeline, said tool comprising; first and second die members each having a pipe closure surface formed thereon; means for mounting said first and second die members with said pipe closure surfaces aligned in a mating relationship and with at least one of said die members movable towards the other die member; means, engaging said mounting means and said movable die member, for urging said die members together with sufficient force to collapse and close a section of plastic pipe disposed between said pipe closure surfaces; and resilient means attached to one of said die members for aligning said tool on said pipe; said resilient means including at least one spring device attached to one of said die members, said spring device having first and second end sections crossing substantially at the lateral center of said pipe closure surfaces, each said end section terminating in an arcuate loop extending beyond the closure surface of said one die member in the absence of pressure applied thereto, said first and second end sections defining a concave cradle centered at the point of crossing and adapted for receiving said pipe therein; whereby during the initial closure phase of said movable die member said spring device aligns said tool on the pipe, and during the final closure phase of the movable die member said first and second end sections are deflected even with said closure surface of said one die member.

Claim 10

A self-aligning shutoff tool for squeezinG closed a section of plastic pipe to temporarily shut off the flow of fluid or gas in a pipeline, said tool comprising; first and second die members each having a pipe closure surface formed thereon; means for mounting said first and second die members with said pipe closure surfaces aligned in a mating relationship and with at least one of said die members movable towards the other die member; means, engaging said mounting means and said movable die member, for urging said die members together with sufficient force to collapse and close a section of plastic pipe disposed between said pipe closure surfaces; and resilient means attached to one of said die members for aligning said tool on said pipe; said resilient means including at least one spring device attached to one of said die members, said spring device having first and second end sections crossing substantially at the lateral center of said pipe closure surfaces, each said end section terminating in an arcuate loop extending beyond the closure surface of said one die member in the absence of pressure applied thereto, said first and second end sections defining a concave cradle centered at the point of crossing and adapted for receiving said pipe therein; whereby during the initial closure phase of said movable die member said spring device aligns said tool on the pipe, and during the final closure phase of the movable die member said first and second end sections are deflected even with said closure surface of said one die member.

Claim 11

The tool of claim 6, wherein a separate spring device is attached to the front and rear surfaces of said one die member, and the first and second end sections of each spring device are slidably mounted on said one die member, whereby said spring devices axially and laterally center said tool on said pipe during the initial closure phase of said movable die member, and said spring devices deflect even with the closure surface of said one die member during the final closure phase of the movable die member.