My invention relates generally to tool joint structure for use in drill pipe employed in drilling oil and gas wells, and particularly to a tool joint pin having release mechanism whereby the tool 6 to which the joint is connected may be easily pulled out of the drill pipe, and an important object of my invention is to provide arrangements of the character indicated above which are adapted to be used on each joint of the drill pipe. Other important objects and advantages of my invention will be apparent from a reading of the following description taken in connection with the drawing, wherein for purposes of illustration I have shown a preferred embodiment of my 16 invention.
In the drawing: Figure 1 is a general transverse vertical sectional view taken through the embodiment and showing the sleeve seated in circulation hole closing position.
Figure 2 is an enlarged sectional elevational view of the dog mechanism.
Figure 3 is an elevational view of Figure 2 taken at right angles thereto.
Figure 4 is a horizontal sectional view taken through Figure 1 approximately on the line 4-4 and looking downwardly in the direction of the arrow.
Referring in detail to the drawing, the numeral 5 generally designates the body of the joint which has an internal threaded flange 6 at its upper end in which the drill pipe 1 is threaded.
A flat helical spring 8 occupies the space between the shoulder 9 defined by the flange 6 and the shoulder 10 defined by a reduced bore portion I1.
The reduced portion II is smooth so as to provide a comparatively frictionless bearing surface for the sleeve 12 which is to be worked up and down in the bore portion II in conjunction with the spring 8 which engages the top of the sleeve 12 so as to normally urge the same to a depressed position in which the beveled lower end 3 of the sleeve seats on the beveled shoulder 14 which joins the lower end of the reduced bore portion 11 all as clearly shown in Figure 1 of the drawing. Below the shoulder 14 the body of the joint has a reduced bore 15 which is axially aligned with and substantially of the same diameter as the bore 16 in the sleeve 12. Adjacent the upper part of the bore in the sleeve .12 is a radially outwardly beveled annular notch 11 which accommodates the releasing dogs 18, 19, respectively, which are pivoted coaxially at opposite sides of the release rod 20 which has an enlarged diameter portion 21 below the pivotal point 22, which enlarged diameter portion normally depends through the sleeve 12 into the reduced bore portion 15 of the tool body and has a pointed lower end 23. Respective links 24, 25 are pivoted at their lower ends to the respective dogs 18, 19, as indicated in Figure 2 of the drawing, at the points designated 26, 21, and the upper ends of these links are pivoted on opposite sides of a collar 29 slidably arranged on the rod 20 above the dogs and within the lower end of the tube 28 which extends up through the drill pipe 7 as indicated in Figure 1 of the drawing so as to be capable of being raised and lowered selectively. When the tube 28 is lowered from the position shown in Figure 2 this engages the links 24 and 25 so as to bring the dogs 18, I toward each other and out of engagement with the annular notch II in the sleeve 12, in which condition the releasing dog assembly may be withdrawn through the drill pipe, or passed down therethrough to occupy a position in the joint 5, as the case may be. With the dog assembly pushed down below the annular groove II, the dogs 18, It may be caused to spread by gravity or the action of the fluid in the drill pipe sufficiently to bear against the beveled face of the groove II to reach the position illustrated in Figure 1 of the drawing and thereby provide for elevating the sleeve 12 by pulling up on the tube 28, to a position in which the circulation holes 30 arranged through the wall of the body 5 above the shoulder 14 are uncovered and circulate water through the joint to release the joint in the event that the same became stuck. The lower end of the joint body 5 is provided with an externally threaded tapered point 31 for connection with the tool (not shown).
Although I have shown and described herein a preferred embodiment of my invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in the structure and arrangement of the parts, within the spirit of the invention and the scope of the subjoined claims.
Having described the invention, what is claimed 46 as new is: 1. A tool joint comprising a tubular body having a stop shoulder within the lower part thereof and below circulation holes formed through the wall of said body, an imperforate sleeve slidable in said body between a position above and exposing said holes to a position in which the lower end of the sleeve engages said stop shoulder and closes said holes, spring means compressed between an upper part of said tubular body and the top of said sleeve and normally holding said sleeve on said stop shoulder, and means freely insertible through the upper end of said body and through said sleeve, said means comprising a carrier including a rod, upwardly extending arns pivoted at their lower ends on said rod, links connected to and between the rod and the arms, and an operator on the rod and engageable with said links for contracting the arms to pass freely through the body and the sleeve, said operator being operable to permit said arms to spread within said sleeve, said sleeve having an internal lift shoulder engageable by said arms in their spread condition upon elevation of said rod to lift said sleeve against the resistance of said spring means and expose said circulation holes.
2. A tool joint according to claim 1 wherein said operator comprises a tube loosely telescoped on said rod and surrounding portions of said links.
3. In a device of the class described, a vertically arranged tubular member having a transverse port therein and a valve seat below the port, a sleeve slidably arranged in the tubular member, spring means for normally holding the sleeve on the seat and closing the port, said sleeve having an internal groove therein forming a downwardly facing shoulder, a rod adapted tobe passed through the tubular member into the sleeve, arms pivoted at the lower ends to said rod and having their upper ends adapted to engage the shoulder for raising the sleeve when the rod is pulled upwardly, links pivoted to intermediate portions of the arms and extending upwardly, means for slidably connecting the upper ends of the links to the rod and a small tubular member passing over the rod and when moved downwardly engaging the links for moving the arms inwardly and clear the shoulder.
sCOTrY ALTON LINNEY.