US3553980A

US3553980A - Kelly bar coupling

Info

Publication number: US3553980A
Application number: US816945A
Authority: US
Inventors: Robert E Dickinson; William P Henson
Original assignee: Mobile Drilling Co Inc
Current assignee: Mobile Drilling Co Inc
Priority date: 1969-04-17
Filing date: 1969-04-17
Publication date: 1971-01-12
Anticipated expiration: 1988-01-12

Abstract

A DRIVE ASSEMBLY FOR AN EARTH DRILLING DEVICE WHEREIN THE LOWER DRIVING SHAFT IS COUPLED TO THE UPPER DRIVEN SHAFT BY A COUPLING WHICH IS SLIDABLY RECEIVED AND RETAINED ON THE UPPER DRIVEN SHAFT. THE ASSEMBLY ALSO INCLUDES A LATCH PIN MOUNTED ON THE COUPLING AND ROTATABLE TO A POSITION LATCHING THE COUPLING IN CONNECTED POSITION OR IN A POSITION ABOVE THE LOWER END OF SAID UPPER DRIVEN SHAFT.

Description

United States Patent O M 1m; cl. riad 1/10 U.s. CLM-23.5 s claims ABSTRACT F THE DISCLOSURE fA drive assemblyfor an earth drilling device wherein the lower driving shaft is coupledto the upper driven shaft-bya coupling which is slidably rreceived and retained-.on the upper driven shaft. The assembly also in`- cludes a latch pin mounted on the coupling and rotatable to a position latching the coupling in connected position or in a position above the lower end of said upper driven shaft. Y

BACKGROND OF THE INVENTION Y. Field ofthe invention This invention relates to a drive assembly.

I. i Description of the prior art i Certain types of vertical portable earth drills include a driven shaft and a driving shaft between which ysome disalignment is expected 'and allowable. Thus in portable earth drilling rigs it is cnunon to connect a vertical drive stud from a gear box mounted on a drill frame, carried by a vehicle, to a vertical Ikelly bar, from which a rotary table is driven. The kelly bar is located above the gear box and is a part of the Vuprightportion of the drill. Such drill rigs incorporate means to fold the upright portion of the drill so-as to'reduce the height of the drill when the lvehicle is moved from place to place. Thus lit is desirable that the coupling between the kelly bar and the gear box be such as to keep as smallV as possible the proportion between the part of the drill that does not fold and the part of the drill that does fold. One example of the prior art in this area is disclosed in the patent to Fehrman et al. 3,309,898, n l

SUMMARY OF THE INVENTION One embodiment of this invention might involveY in a drive assembly for use with an earth drilling device including a lower shaft, an upper shaft, said upper shaft adapted to be swung away from said lower shaft, and a coupling interconnecting said shafts, said coupling including an upper section having a hub portion which has a noncircular hole through it conforming in shape and size to a cross section of a lower end of said upper shaft and adapted to slidably receive said lower end, and a lower section having a hub portion which has a noncircular hole through it conforming in shape and size to a cross section of an upper end of said lower shaft and adapted to slidably receive said upper end, said upper conforming hole being smaller in each corresponding cross sectional dimension than said lower conforming hole, the improvement which comprises abutment means fixed to the lower end of said upper shaft and extending radially outwardly Y 3,553,980 Patented Jan. 12, 1971 ICC Another object of this invention is to provide a reliable coupling which does not have a tendency to become disconnected during operation.

Still another object of this invention is to provide an improved drill assembly.

A further object of this invention is to provide a coupling which is capable of accommodating misalignment.

Still a further object of this invention is to provide a portable earth drill drive which permits quick and easy connection and disconnection of a kelly bar and a drive train.

Related objects and advantages will be apparent as the description proceeds.

BRIEF DESCRIPTION OF THE DRAWING y FIG. l is a side elevation partially in section of the coupling of the present invention.

FIG. 2 is a top plan view with the kelly bar removed of the coupling of the present invention.

FIG. 3 is an enlarged section taken along the line 3-3 of FIG. 2 in the direction of the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularly to the drawings, there is illustrated a driving shaft 10` which is coupled to a kelly bar or driven shaft 11 by means of the coupling 12. The driving shaft 10 is cylindrical in outer configuration and is keyed to a generally externally square shaped `member 15 by means of keys 16 received within suitable grooves in both the shaft 10 and the externally square shaped member 15. The kelly bar 11 is also externally square shaped but has a smaller externally square shaped size than does the externally square shaped member 15. For the purposes of this description, the

members

10 and 15 are considered to be a composite driving shaft.

The coupling 12 includes an upper section 17 and a lower section 20. The upper section 17 has a hub portion 21 which has a square shaped hole 22 through it conforming in size and shape to a cross section of the lower end of the kelly bar 11 and adapted to slidably receive the lower end of the kelly bar 11. Fixed to the lower end of the kelly bar 11 by a screw 25 is a at round (cylindrical) disc 26 which acts as an abutment limiting the downward axial movement of the coupling 12. Thus, the coupling 12 is shown in its lowenmost position in FIG. l, the coupling being movable upwardly on the kelly bar to various other positions above the illustrated position.

The lower section Z0 of the coupling also has a hub portion 30 which has a square shaped hole 31 through it conforming in size and shape to the external configuration of member 15. When the member 15 is received within the hole 31 the coupling is slidable up and down relative to the member 15. In one specific embodiment of the invention, the external size of the member 15 is three inches lwhile the internal dimension of the hole 31 is between 3.030 and 3.040 inches. Thus, it can be appreciated that a relatively loose connection is provided between the member 15 and the coupling 12.

A latch pin 50 is rotatably mounted within a bore 51 in the hub 21. The bore 51 intersects the upper hole 22. The latch pin 50 includes a latch 52 which is flattened on one side at 55 but which has its full cylindrical shape at the other sides thereof, such as, for example at the side 56. Fixed to the latch pin 50 is a lever `60 which permits rotating of the latch pin to the non-latched position illustrated in FIG. 1 or to a position in which the portion 56 of the latch projects into one or the other of a pair of

recesses

58 and 59 in the kelly bar. When the latch 52 is projected into the recess 58, the coupling 12 is locked in the position of FIG. 1. When the latch 52 is projected into the recess 59, the coupling is locked in a position such that the lower end ofthe coupling is above the plate 26. Each of the

recesses

58 and 59 has a complementary configuration to the latch cylindrical shape `56.

A screw 61 has received therein a spring 63 which acts against a ball 65 retained -within the recess 66 in the screw by means of inturned end `67. The ball 65 acts as a detent by engaging one or the other of a pair of bores 70 and 71 in the latch pin 50. A jam nut 62 is received upon the screw 61 and is used to lock the screw in any desired position providing the proper amount of spring action retaining the latch pin in one or the other of the positions indicated by the reception of the bale 65 in either of the bores 70 or 71. In order to maintain smooth action of the latch pin, a zerk fitting 75 is provided in the end of the latch pin so as to make possible placing grease or other lubricating material into the interior of the latch pin for lubricating the bores 70 and 71. A suitable passage 74 leads from the zerk fitting to the bores 70 and 71.

The coupling 12 is provided with an external cylindrical outwardly projecting flange 100 which may be engaged or grasped by the operator to lift the coupling or to move it between the positions determined by the recesses or

grooves

58 and 59 in the kelly bar.

It will be evident from the above description that the present invention provides an improved coupling which remains coupled to a portion of the structure when the coupling is disconnected as well as when the coupling is connected so as to prevent loss of the coupling. It will also be evident that, by the provision of the groove 58 and the latch pin 50, means are provided for retaining the coupling coupled by keeping the coupling down against the plate 26 so that jiggling or misalignment of the coupling does not cause the coupling to disconnect. The different in sizes of the hole 31 and the member 15 also permits misalignment of the coupling and the driving shaft. It can also be appreciated that the present invention also permits easy and quick disconnection of the driving and driven shafts.

The invention claimed is:

1. In a drive assembly for use with an earth drilling device including a lower shaft, an upper shaft, said upper shaft adapted to be swung away from said lower shaft, and a coupling interconnecting said shafts, said coupling including an upper section having a hub portion which has a noncircular hole through it conforming in shape and size to a cross section of a lower end of said upper shaft and adapted to slidably receive said lower end, and a lower section having a hub portion which has a non-circular hole through it conforming in shape and size to a cross section of an upper end of said lower shaft and adapted to slidably receive said upper end, said upper conforming hole being smaller in each corresponding cross sectional dimension than said lower conforming hole, the improvement which comprises abutment means fixed tothe lower end of said upper shaft and extending radially outwardly beyond the lower end of said upper shaft, said abutment means being sized smaller than the lower section hole and received therein to limit the downward axial movement of said coupling.

2. The drive assembly of claim 1 additionally comprising a latch pin rotatably mounted in said coupling, a latch on said latch pin, said upper shaft having a first groove therein, said latch pin being rotatable between two positions in one of which said latch projects into said upper hole and is in said groove so that said upper driven shaft is locked against axial movement relative to said coupling and in the other of which said latch is withdrawn into said coupling and does not project into said upper hole so that said coupling is movable axially .relative to said upper shaft, a lever fixed to said latch pin for rotation thereof, and a ball detent in said coupling, said latch pin having a pair of recesses therein one of which is engaged by said ball when said latch pin is in one of said positions and the other of which is engaged by said ball when said latch pin is in the other of said positions, and spring means acting between said ball and coupling and yieldably maintaining said ball in said recesses for yieldably retaining said latch pin in said positions.

3. The drive assembly of claim 2 wherein said upper shaft has a second groove spaced from and above said first groove and so positioned that, when said latch is in said second groove, said coupling is positioned above the lower end of said upper shaft.

4. The drive assembly of claim 3 wherein said abutment comprises a at round disc fixed to said upper shaft by a screw coaxial with said -upper shaft.

5. The drive assembly of claim 1 wherein said abutment comprises a flat round disc fixed to said upper shaft by a screw coaxial with said upper shaft.

References Cited UNITED STATES PATENTS 2,695,504 ll/ 1954 Magee 64--23 2,787,144 4/1957 Chauvel 64-23 2,885,231 5/1959 Smith 6423.5X

JAMES A. WONG, Primary Examiner