US 1334487 A
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Description (OCR text may contain errors)
C. R. EDWARDS.
UNSCREWING DEVICE FOR PIPE JOINTS.
APPLICATION FILED AUG.41 |919.
C. R. EDWARDS. UNSCREWING DEVICE FOR PIPE JOINTS.
APPLIcATxoN FILED AuG.4. |919.
1,334,487. Patented Mm=.23,1920.
2 SHEETS-SHEET 2.
pivoted at-opposing points to the inner wall of the section 1. The operative faces of said dogs are serrated so as to more readily engage with the casing or the wall ofthe bore.
The lower end of the section 2 is reduced forming the outwardly threaded neck 23,
-which may beyscrewed directly into the section of pipe to be backed off or unscrewed or which may receive a fishing tool o-f any conventional form for engagement with the pipe.
The device is"iirst attached to a string of pipe whose sections are connected by means of collars having right hand threads, and
cated by the arrows i-n Fig. 2. The section 2 will be temporarily held against rotation, during this movement, on account of its friction with the section of pipe upon which it is resting, and the section 1 will be held against rotation by reason of its friction with the section 2. The lsection 1, being -thus held, will cause the spur gears 16 to travel around the rack face 17 in the direction indicated by the arrows in Fig. 3, thus forcing the levers 21 and the dogs 22 outwardly through the wide slots 24, 24, which are cut through opposing sides of the section l, causing the dogsv22, 22, to engage with the casing wall, or in the absence of casing, with the walls of the bore, and the section 1V will thus be firmly held against rotation in the bore. A continued rotation of the shaft 6 will be transmitted through the spur gears 16 and 19 and the shafts 15 to the section 2, turning it in the opposite or left hand direction and causing the same to engage with the adjacent section of the drill stem and rotate the same backwardly, thus unscrewing the same from the sections underneath and when unscrewed, the same may. be withdrawn from the bore.
What I claim is:
1.- A device for unscrewing pipe in a well bore, including two independently rotatable members, a drlving shaft, means operatively `connecting said shaft with one of said member and actuated by said means into engage- `ment v'with the walls of the bore, whereby said last mentioned member is anchored against rotation.
2. A device for unscrewing pipe in a well bore, including an inolosed caslng formed of two independently rotatable sections, a driving shaft having-bearings in said sections, means operatively connecting said tation.
3f A device for unscrewing pipe in a well bore, including a casing formed of two independently rotatable sections, a driving shaft, extending through the casing and having bearings in the respective sections thereof, engaging members carried by one of said sections, means operatively connecting said shaft with said engaging members and with the other section, said means being actuated by said shaft to force said members into engagement with the walls of the bore whereby the-first mentioned section is anchored against rotation, and the continued rotation of said shaft thereafter operating through said means to rotate the other section reversely with respect to the directio of the rotation of said shaft:
` 4. A device for unscrewing pipe in a well bore, including a casing formed of two independently rotatable sections, a Vdriving shaft extending through the casing, engaging dogs carried by one section of the easing, means operatively connecting said shaft with said dogs whereby the rotation of the shaft relative to the casing will actuate said y dogs into engagement with the well bore,
thereby anchoring said section against rotation, said means being also operatively connected wlth the other sectlon and operating through the shaft to drive the other section of the casing, reversely lwith respect to the shafts rotation when said first mentioned section is anchored against rotation. In testimony whereof he has signed his name to this specification in the presence of two subscribing witnesses.
CHI-IARLES R. EDWARDS. Witnesses IRENE I. BRUNs, ELLIE MESCHKAT.