US2935871A

US2935871A - Well logging apparatus

Info

Publication number: US2935871A
Application number: US577232A
Authority: US
Inventors: Robert G Pearson
Original assignee: GEOLOGRAPH SERVICE CORP
Current assignee: FIRST ASSET-BASED LENDING GROUP Inc C/O CONSOLIDATED ASSET MANAGEMENT COMPANY 120 NORTH ROBINSON OKLAHOMA CITY OK 73192
Priority date: 1956-04-10
Filing date: 1956-04-10
Publication date: 1960-05-10
Anticipated expiration: 1977-05-10

Description

May 10, 1960 PEARSQN' 2,935,871

WELL LOGGING APPARATUS Filed April 10. 1956 3 Sheets-Sheet 1 FIG. 5

FIG 7 94 10a FIG- 1 INVENTOR ROBERT G. PEARSON BY% J M;

' ATTORNEYS May 10, 1960 R. G. PEARSON 2,935,871

WELL LOGGING APPARATUS Filed April 10, 1956 s Sheets-Sheet 2 FIG. 2 INVENTOR ROBERT G. PEARSON ATTORNEYS May 10, 1960 R. G. PEARSON WELL LOGGING APPARATUS 3 Sheets-Sheet 3 Filed April 10, 1956 FIG- 3 FIG. 4

INVENTOR ROBERT G. PEARSON WM,WV/aw 4 ATTORNEYS United States Patent WELL LOGGING APPARATUS Robert G. Pearson, Oklahoma City, Okla., assignor to Geolograph Service Corp., Oklahoma City, Okla., a corporation of Oklahoma This invention relates to a mechanical device for recording the progress of drilling operations in the drilling of oil and gas wells.

There have been many devices proposed to log the drilling progress of well drilling apparatus. The more recent of these devices have been electromechanical devices having great sensitivity. While these electromechanical devices produce what appear to be very accurate records of the drilling operations, they are so delicate that they are to a great extent unsatisfactory for use under conditions in the field, where they get rough treatment from the drilling crews and where they are generally placed immediately adjacent a drilling rig and thereby subject to considerable jarring and pounding during the operation of the rig. In addition to the fact that this type of apparatus easily gets out of adjustment or frequently breaks down and is therefore in constant need of service by highly skilled specialists, the locations in which such devices would normally be used are in areas where electricity is not readily available. Their use thus requires batteries or generators in addition to those necessary to provide electric light for nighttime operation of the drilling rig. The cost of running such a generator during the day merely to supply an electromechanical well logging device in addition to the losses caused by delays incident to repairs and adjustment largely offset any advantage that may be obtained by the use of electromechanical devices.

On the other hand, the fully mechanical well logging devices at present in use merely record the rate of pene tration of the drill bit by making a mark on a strip of paper moving at a constant speed at the completion of each foot of hole which is drilled. In order to utilize the record, it is desirable that the rate of penetration be expressed graphically, and in order to produce such a graph, the person using the information recorded by the usual mechanical well logging device must convert it into a graph by a laborious and time consuming manual process.

'It is therefore an object of the present invention to provide a well logging device which overcomes the drawbacks of the above described well logging devices.

It is a further object of this invention to provide a fully mechanical well logging device which is dependable in operation and is easily serviced by one familiar with mechanical devices.

It is a still further object of the present invention to provide a well logging device which records the rate of penetration of a drill bit in graph-like form as a function of the time and the depth drilled.

Other and further objects of the present invention will become apparent from the following specification taken together with the appended claims and the accompanying drawings, which show a preferred embodiment of the device, and in which:

Fig. 1 is a diagrammatic view of the manner of connecting the device to a drilling rig;

Fig. 2 is a plan view of the device;

2,935,871 Patented May 10, 1960 Fig. 3 is an elevation view taken along line 33 of Fig. 2;

Fig. 4 is an elevation view of part of the device taken along line 4-4 of Fig. 2;

Fig. 5 is an elevation view of part of the device taken along line 55 of Fig. 2;

Fig. 6 is an elevation view of a part of the device taken along line 66 of Fig. 2; and

Fig. 7 is an elevation view of the device taken along line 77 of Fig. 2.

Referring to the drawings in which like reference numerals indicate like parts, the device is mounted in a box-like container 10 having a front wall 7, a rear wall 8 and side walls 9 and 11, and is closed by a bottom 20 but is open at the top, and which container is partitioned into two sections A and B by a partition 12 which runs transversely of the container.

A horizontal shaft 18 is journaled in the front wall 7 and the rear wall 8 and extends through the center of the section A adjacent the bottom 20'. Means o'perative in response to the movement of the traveling blocks in a drilling rig is provided in the form of a grooved pulley 22 rotatably mounted on the end thereof adjacent the front wall 7. The device is placed adjacent the base of a drilling rig, as shown in Fig. 1, and a wire line 24 is passed around the grooved pulley 22, and one end is led upwardly along one side of the rig over a pulley 19 mounted near the top of the rig and then downwardly to the traveling blocks 26. The other end is led upwardly along the side of the rig and over a pulley 17, mounted on the side of the rig below the pulley 19, and then to a weight 15 'slidably mounted on an inclined guy wire 14. The weight 15 tends to slide down the guy wire 14 under the influence of gravity and serves to keep the wire line 24 taut at all times and thus insure that the pulley 22 is responsive to any movement of the wire caused by the movement of the traveling blocks 26. Pulley 22 is of a size such that when the traveling block moves one foot, the pulley is revolved one-half revolution.

A gear wheel 23 is rotatably mounted on the shaft 18 immediately adjacent the pulley 22 and is loosely connected to the pulley 22. Projecting lugs 25 are mounted on the sides of the pulley 22 and the gear wheel 23 which face each other, and are located the same radial distance from shaft 18. These lugs will thus contact each other when the pulley 22 is rotated relative to the gear wheel. This type of connection between the pulley 22 and gear 23 prevents the normal vibration of the traveling blocks 26 and line 24 from being transmitted to the shaft 18.

On the opposite side of the gear wheel 23 from the pulley 22 is provided means for disengageably connecting the shaft 18 to the gear wheel 23 in the form of a friction clutch 27 which is 'slidably mounted on the shaft 18 and has a clutch face 271; adjacent the face of the gear wheel 23. A shoulder 31 is provided on the shaft 18 and is spaced from clutch 27. A spring 29 is mounted between the shoulder 31 and the friction clutch 27 urging the friction clutch into engagement with the gear wheel 23. Spaced from the friction clutch '27 and the stop 31 is located a disc 38 which is fixed to the shaft 18 approximately midway of its length. Two diametrically opposed lugs or actuating arms 37 project outwardly from the disc 38 and extend to a point beneath the free end of a ratchet support 36 (later to be described). The disc 38 together with the lugs 37 constitute an eccentric means for actuating the ratchet support 36.

Above the disc 38 is a shaft 39 which runs perpendicularly to the shaft '18 and is mounted at one end in the side wall 9 and at the other end in the partition 12. Rotatably mounted on shaft 39 is a drilling rate recording drum 28, one end of which is formed by a gear wheel 30.

Ratchet means are provided which are actuated by the disc 38 to index drum 28. Pivoted to the partition 12 is ratchet support 36, and adjacent the free end thereof is mounted an upright extension 36a. Beneath the ratchet support 36 is a stop 41 supported on the bottom 20, which stop prevents the ratchet support from pivoting downward past the horizontal position. Over the upper end of the upright extension 36a is a second extension 36b slidable in a groove in guide block 390 mounted on partition 12 and surrounding shaft 39. Extension 36b is in sliding contact with extension 36a. On extension 36b is pivoted a dog 31a which is engaged with the teeth of a ratchet wheel 32. Ratchet Wheel 32 is mounted on a ratchet wheel shaft 33 which is rotatably mounted in the partition 12, and extends to a point immediately beneath the gear wheel 30. On the end of the shaft 33 is a small gear 34 engaged with the gear wheel 30.

Two tracks 48 extend'transversely of the section A parallel to the shaft 39 and on substantially the same level as shaft 39. Their ends are mounted in side wall 9 and partition 12. A rack 46 having a length at least as long as the length of the drum 28 and having teeth on both sides thereof is slidably mounted on the tracks 48. Projecting upwardly from one end of the rack 48 is a scriber support 49 which supports a pen or scriber 58 which extends over the drum 28 and contacts the surface thereof.

Stop means in the form of a stop 68 is mounted on one of the tracks 48 adjacent one end of the drum 28. Between the ends of the tracks 48 in the partition 12 is mounted means for urging the rack against the stop means in the form of a pulley 51, over which is guided a wire 50 from which is hung a weight 53. The other end of the wire 50 is attached to the rack 46.

Means are provided for driving the rack along the track in opposition to the effect of weight 53. Extensions 48a project downwardly from beneath tracks 48, and an axle 52 is journaled therein. A pinion 54 is mounted on shaft 52 between the tracks 48 and meshes with the teeth on the bottom of the rack 46. Shaft 52 extends toward the rear wall 8, and has mounted on the end thereof a second clutch 56.

On the rear wall 8 is mounted a bracket 43 in which is rotatably supported a vertical shaft 42. Attached to the vertical shaft 42 is a clock mechanism 40, from which a shaft 44 projects in alignment with shaft 52. Shaft 44 is connected to clutch 56.

There is also provided means for disengaging the clock mechanism from the rack. A second shaft 66 extends downwardly from the bottom of the clock 40. Attached to the shaft 18 beneath the clock 40 is a second disc 64 having diametrically opposed arms 64a projecting therefrom which contact shaft 66. Disc 64 is out of alignment with the shaft 66 in a direction towards the disc 38. The disc 64 together with its arms 64a constitute an eccentric means for actuating the shaft 66.

Adjacent the end of the shaft 18 where it is journaled in the end wall of the section 14 is a gear 86. Mounted on the end wall is a counter device 88 having a shaft with a gear 87 thereon, the

gears

86 and 87 meshing with each other.

Means are also provided for disconnecting the device from the pulley moving in response to the movement of the traveling blocks and simultaneously retaining the rack in the position occupied at the time of disconnection. Beneath the clutch 27 is a lever shaft 74 which extends transversely of the section A and has one end journaled in the partition 12 and the other end journaled in side wall 9. The end of shaft 74 projects outside of the container 10, and has attached thereto a lever 72. Immediately beneath the clutch 27 is a clutch engaging arm 76 rigidly attached to shaft 74 and projecting upwardly into a groove 78 in the clutch 27. 4

Mounted on the rear wall of the section A adjacent the edge of the clock mechanism 40 is a pulley 81, A

'4 wire 80 is passed over pulley 81 and has one end connected to the clock mechanism 40 and the other end connected to the lever 72. A spring 75 is connected between the end of the lever 72 opposite the shaft 74 and the frame 10 urging the end of the lever 72 upwardly.

Mounted between the tracks 48 adjacent the frame 10 is a shaft 84 spring loaded by coil spring 84a on which is mounted a bell crank 85. One arm of the bell crank extends substantially horizontally over the upper face of the rack 46, and has a point 83 extending downwardly therefrom. The other end of the bell crank 85 has connected thereto a wire 82 which extends downwardly to a pulley 73, mounted on a frame member 71 from side wall 9 near the bottom 20 and then upwardly where it is connected to the lever 72.

The operation of the apparatus is believed to be evident from the foregoing description. When the traveling blocks 26 move downwardly as the drill penetrates the earth, the wire line 24 engaged with the pulley 22 rotates the pulley 22 and causes the engagement of the projecting lugs 25 with the corresponding projecting lugs on the gear wheel 23. The lever 72 is permitted to remain in its upward position, and is retained in this position by spring 75. Spring 29 thus urges the clutch 27 into engagement with the gear wheel 23, thereby coupling the shaft 18 to the pulley 22.

Disc 38 is revolved by shaft 18, and at each half revolution, one of the opposed lugs 37 on the disc 38 engages the free end of the ratchet support 36, pivoting it upwardly about the pivotal connection of the ratchet support to the partition 12. As the ratchet support 36 is moved upwardly, the dog 31a on the upper end of extension 36b engages the teeth of ratchet wheel 32, and revolves the ratchet wheel 32 together with shaft 33 and small gear 34 until the lug 37 is withdrawn from beneath the ratchet support 36 by reason of the continued rotation of disc 38. Ratchet support 36 then falls back to its initial position where it is supported by stop 41, while the ratchet wheel 32, the shaft 33 and the gear 34 remain in their rotated position. Rotation of the gear 34 rotates the drum 28 by means of the gear wheel 30.

Thus, for each half revolution of the shaft 18, the drum 23 is rotated a specified amount, depending upon the dimensions of the ratchet wheel 32, the gear 34 and gear wheel 30.

The clock mechanism 40, in the meantime, is positioned with the clutch 56 engaged with the shaft 52. During the engagement of the clutch 56, the shaft 52 is rotated, thus rotating pinion 54, which in turn drives the rack 46 and the scriber 58. The direction of the rotation of shaft 52 is such that the rack is driven in the direction of arrow 62 (Fig. 2). As it moves in this direction, the rack lifts the weight 53.

The disc 64 is positioned on shaft 18 so that at the same time one of the lugs 37 on disc 38 engages the ratchet support 36, one of the projecting arms 64a engages the second shaft 66 extending downwardly from beneath the clock. The projecting arm 64a engages the second shaft 66 and pivots the clock around a vertical shaft 42 towards the rear wall 8, thus disengaging clutch 56. When clutch 56 is disengaged, weight 53 returns rack 46 to its position against the stop 68.

Thus it is seen that at the same time the drum is indexed for each half revolution of the shaft 18, the rack 46 which carries the scriber 58 is returned to its starting position. Since the pulley 22 is of a diameter such that it revolves one half revolution for every foot the traveling blocks move, the drum 28 is indexed each time the traveling blocks move one foot and the scriber 58 is returned to its starting position at the end of each foot drilled.

By reason of this operation, there is produced a series of lines on the drum, as shown at 70. Each line represents the length of time required to drill one foot, and by connecting the ends of the lines, there is produced a graph of the drilling operation which is a function of the time and the distance drilled.

In practical operation, graph paper may be placed around the drum, and the record made directly on the graph paper. Conventional means for providing ink at the point of the scriber may be provided.

When it is desired to disengage the recording apparatus from the traveling block, for instance when it is necessary to withdraw the bit and replace it, the lever 72 is pressed downwardly against the action of spring 75. Three actions take place simultaneously. The arm 76 mounted on shaft 74 and engaged in groove 78 in the clutch 27 pivots to move the clutch face 27a away from gear wheel 23, thus disengaging shaft 18 from pulley 22. The lever 72 tensions the wire 80, thus pivoting clock mechanism 40 about vertical shaft 42 to disengage clutch 56. The rack mechanism is therefore stopped in its motion. At the same time wire 82 is slackened, thus permitting bell crank 85 to be pivoted on shaft 84 between the tracks 48 under the action of the coil spring 84a. The point 83 on the end of one arm of the bell crank engages the rack 46, thus preventing the weight 53 from returning the rack to its starting position. Thus, at the same time that the clutch 27 is disengaged, the scriber is stopped at the precise point in the foot then being drilled where the clutch 27 was disengaged.

The drilling operation can thus be interrupted at any point without requiring any special adjustments on the recording mechanism to take into effect the period during which no drilling is being carried on. When drilling operations commence again, lever 72 is released, and the reverse of the above described operations takes place, and the recording apparatus begins recording the operation at the precise point where it left oflf.

It has also been found desirable to make a record of the actual time spent in drilling as well as the number of times which the traveling blocks are raised and lowered and the time spent in this particular operation. In the section B of the device there is provided a part of the apparatus which makes a record of these items.

Mounted between the front wall 7 and a hanger 99 projecting from the partition 12 into the section B is a longitudinal shaft 96 on which is mounted a second gear wheel 98. This second gear wheel 98 extends through an aperture 97 in the partition 12 and meshes with gear wheel 23 on the shaft 18. Adjacent the end of the longitudinal shaft 96 is a transverse shaft 102 which is rotatably mounted between the partition 12 and the side wall 11, and which has an enlarged portion 103 with a plurality of screw threads thereon. The end of longitudinal shaft 96 carries a bevel gear 100 which meshes with bevel gear 101 mounted on transverse shaft 102.

A block 104 having a threaded bore therethrough is mounted on the enlarged portion 103 of transverse shaft 102 with the threads in the bore engaged with the threads on the enlarged portion 103. Arms 105 project from either side of the block 104 and slide on supports 106 which are mounted between partition 12 and side wall 11 on each side of transverse shaft 102 and are parallel therewith. Block 104 carries a second scriber 108. The longitudinal and transverse shafts, the enlarged portion of the transverse shaft and the supports thus form means for driving the scriber in response to the movement of pulley 22.

Shaft 92 is rotatably mounted on side wall 11 and a drilling distance recording drum 90 is mounted thereon, and has a chart 110 positioned thereon against which the scriber 108 bears. Mounted on partition 12 are means for driving the drum 90 at a constant speed in the form of a clock mechanism 94 having a shaft 95 projecting therefrom. Shaft 95 is coupled to shaft 92 by coupling 93.

In the operation of this part of the recording device, the clock mechanism 94 drives the drum 90 at a constant rate of speed. The rotation of pulley 22 caused 6 by the wire line 24 during the movement of the traveling blocks 26 is transmitted through the gear wheel 23 to the gear wheel 98. Shaft 96 rotates the shaft 102 through the bevel gears and 101, thus rotating the enlarged section 103 to move the block 104 and the scriber 108 along the surface of the drum 90.

Since the clutch 27 does not disengage the gear wheel 23 from pulley 22, the record on the chart 110 will be continuous. Thus, when the traveling blocks 26 are lowered to lower the drill bit into the well, a substantially straight line will be made along the chart 110 in. a direction parallel to the axis of the shaft 92, the line slanting slightly because of the length of time necessary to lower the traveling blocks during which the clock mechanism will rotate the drum 90 a short distance. During the drilling operation, the actual amount of penetration will be recorded as well as the time required for this penetration. When the traveling blocks are raised, a second substantially vertical line will occur on the chart 110 representing the time and the distance required for the movement of the traveling blocks.

There has thus been provided a fully mechanical well logging device which is very accurate in its operation, and yet is simply constructed and easily maintained by anyone familiar with mechanical devices. The record produced by the part of the device recording the time required to drill each foot of well is readily converted into a graph, and the part of the device recording the time required for the entire drilling operation, the distance actually drilled, and the number of trips made by the traveling blocks is constantly connected to the drilling rig.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the form hereinbefore described and illustrated in the drawings being merely a preferred embodiment thereof.

Having thus disclosed the invention, What is claimed 1s:

1. A well logging device comprising means responsive to the movement of the traveling blocks in a drilling rig, a shaft in axial alignment with said responsive means, means for disengageably coupling said shaft to said responsive means, eccentric means on said shaft, ratchet means actuated by said eccentric means, a drilling rate recording drum rotatably mounted adjacent said ratchet means indexed by said ratchet means, a pair of tracks parallel to the axis of said drum and adjacent thereto, a rack having teeth on both sides thereof and at least as long as said drum slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, stop means on one of said tracks adjacent the end of said drum, means for urging said rack against said stop means, means for driving said rack along said tracks at a constant rate of speed, a spring loaded lever pivotally mounted adjacent said shaft, said coupling means being actuated by said lever for disengaging said shaft from said responsive means, means actuated by said lever for disengaging said rack driving means from said rack, means actuated by said lever for retaining said rack in the position it occupies when said lever is actuated, a longitudinal shaft rotatably mounted adjacent said responsive means and connected thereto, a transverse shaft rotat ably mounted transversely to the end of said longitudinal shaft having an enlarged threaded portion thereon and geared to said longitudinal shaft, a block having a thread ed bore therein mounted on said enlarged threaded portion with the threads of the bore engaged with the threads on said enlarged threaded portion, support means on each side of said transverse shaft on which said block is supported, a second scriber mounted on said block, a drilling distance recording drum rotatably mounted with the axis thereof parallel to the axis of said transverse shaft and the surface of which is contacted by said second scriber, and means for rotating said drilling distance recording drum at a constant rate of speed.

2. In a well logging device having a wire line connected to traveling blocks in a drilling rig, a pulley wheel around which said wire line passes, and means for keeping said wire line tight around said pulley, the combination of a gear wheel in axial alignment with said pulley, means connecting said pulley and gear wheel, a rotatable shaft in axial alignment with said pulley and gear wheel, a clutch on said shaft engageable with said gear wheel for coupling said shaft to said gear wheel, eccentric means on said shaft, ratchet means actuated by said eccentric means, a drilling rate recording drum rotatably mounted adjacent said ratchet means and indexed by said ratchet means, said ratchet means when actuated moving said drum through a predetermined angular movement, a pair of tracks parallel to the axis of said drum and adjacent thereto, a rack having teeth on both sides thereof and at least as long as said drum and slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, stop means on one of said tracks adjacent the end of said drum, means for urging said rack against said stop means, an axle rotatably mounted beneath said tracks, a pinion on one end thereof engaged with said rack, a clock mechanism connectable to said axle for driving said rack and said scriber at a constant rate of speed, said clock mechanism being pivoted for movement for disconnecting said clock mech anism from said axle, a second eccentric means on said shaft engageable with said clock mechanism for pivoting said clock mechanism when said drum is indexed, a spring loaded lever pivotally mounted adjacent said clutch for disengaging said clutch, a wire connected between the free end of said lever and said clock mechanism for disconnecting said clock mechanism from said axle when said lever is actuated so as to disengage said clutch, means actuated by said lever for retaining said rack in the position it occupies when said lever is actuated, a longitudinal shaft rotatably mounted adjacent said gear wheel, a second gear wheel mounted on said longitudinal shaft and meshed with the first said gear wheel, a bevel gear on the end of said longitudinal shaft, a transverse shaft rotatably mounted transversely to the end of said longitudinal shaft and having an enlarged threaded portion thereon, a second bevel gear on said transverse shaft meshed with the bevel gear on said longitudinal shaft, a block having a threaded bore therein and having support arms projecting from either side thereof, said block being mounted on said enlarged threaded portion with the threads of the bore engaged with the threads on said enlarged threaded portion, supports mounted one on each side of said transverse shaft and parallel thereto on which the projecting support arms rest, a second scriber mounted on said block, a drilling distance recording drum rotatably mounted with the axis thereof parallel to the axis of said transverse shaft and the surface of which is contacted by said second scriber, and a second clock mechanism for rotating said drilling distance recording drum at a constant rate of speed.

3. In a well logging device having a wire line connected to traveling blocks in a drilling rig, a pulley wheel around which said wire line passes, and means for keeping said wire line tight around said pulley, the combination of a gear wheel in axial alignment with said pulley, a rotatable shaft in axial alignment with said pulley and gear wheel, means for disengageably connecting said gear wheel to said pulley, a clutch on said shaft engageable with said gear wheel for coupling said shaft to said gear wheel, eccentric means on said shaft, ratchet means actuated by said eccentric means, a drilling rate recording drum rotatably mounted adjacent said ratchet means and indexed by said ratchet means, a pair of tracks parallel to the axis of said drum and adjacent thereto, a rack having teeth on both sides thereof and at least as long as said drum and slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, stop means on one of said tracks adjacent the end of said drum, means for urging said rack against said stop means, an axle rotatably mounted beneath said tracks, a pinion on one end thereof engaged with said rack, a clock mechanism connectable to said axle for moving said rack at a constant rate of speed, a second eccentric means on said shaft engageable with said clock mechanism for disconnecting said clock mechanism from said axle when said drum is indexed, a spring loaded lever pivotally mounted adjacent said clutch for disengaging said clutch, a wire between the free end of said lever and said clock mechanism for disconnecting said clock mechanism from said axle when said clutch is disengaged, means actuated by said lever for retaining said rack in the position it occupies when said lever is actuated.

4. In a well logging device having a wire line connected to traveling blocks in a drilling rig, a pulley wheel around which said wire line passes, and means for keeping said wire line tight around said pulley, the combination of a shaft in axial alignment with said pulley, means for disengageably coupling said shaft to said pulley, eccentric means on said shaft, ratchet means actuated by said eccentric means, a drilling rate recording drum rotatably mounted adjacent said ratchet means and indexed by said ratchet means, a pair of tracks parallel to the axis of said drum and adjacent thereto, a rack having teeth on both sides thereof and at least as long as said drum slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, stop means on one of said tracks adjacent the end of said drum, means for urging said rack against said stop means, means for driving said rack along said tracks at a constant rate of speed, means on said shaft for disengaging said rack driving means from said rack when said drum is indexed, a spring loaded lever pivotally mounted adjacent said shaft, said coupling means being actuated by said lever for disengaging said shaft from said pulley, means connected between one end of said lever and said rack driving means for disengaging said rack driving means from said rack when said lever actuates said coupling means, and means actuated by said lever for retaining said rack in the position it occupies when said lever is actuated.

5. A well logging device comprising means responsive to the movement of the traveling blocks in a drilling rig, a shaft in axial alignment with said responsive means, means for disengageably coupling said shaft to said responsive means, eccentric means on said shaft, ratchet means actuated by said eccentric means, a drilling rate recording drum rotatably mounted adjacent said ratchet means and indexed by said ratchet means, said ratchet means when actuated moving said recording drum a predetermined angular amount, a pair of tracks parallel to the axis of said drum and adjacent thereto, arack having teeth on both sides thereof and at least as long as said drum and slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, stop means on one of said tracks adjacent the end of said drum, means for urging said rack against said step means, means for driving said rack along said tracks at a constant rate of speed, means on said shaft for disengaging said rack driving means from said rack when said drum is indexed, a spring loaded lever pivotally mounted adjacent said shaft, means actuated by said lever for disengaging said shaft from said pulley, means actuated by said lever for disengaging said rack driving means from said rack when said shaft is disengaged from said pulley, and means actuated by said lever for retaining said rack in the position it occupies when said lever is actuated.

6. In a well logging device the combination of a wire line connected to traveling blocks in a drilling rig, a pulley wheel around which said wire line passes, means for keeping said wire line tight around said pulley, a gear wheel in axial alignment with said pulley, means connecting said pulley and gear wheel, a rotatable shaft in axial alignment with said pulley and gear wheel, a first clutch on said shaft engageable with said gear wheel for coupling said shaft to said gear wheel, a first disc on said shaft, two diametrically opposed lugs projecting from opposite sides of said disc, ratchet means actuated by said lugs, a drilling rate recording drum rotatably mounted adjacent said ratchet means and indexed by said ratchet means, said ratchet means when actuated rotating said recording drum a predetermined angular amount, a pair of tracks parallel to the axis of said drum and adjacent thereto, a rack having teeth on both sides thereof and of a length substantially equal to the length of said drum and slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, a stop on one of said tracks adjacent the end of said drum, means for urging said rack against said stop, an axle rotatably mounted beneath said tracks, a pinion on one end thereof engaged with said rack, a second clutch on the other end of said axle, a clock mechanism having a shaft axially aligned with said axle and connected to said second clutch for driving said rack at a constant rate of speed, said clock mechanism being pivoted for movement out of alignment with said axle for disengaging said second clutch, said clock having a downwardly extending arm thereon, a second disc on said shaft having a pair of diametrically opposed arms thereon engageable with said downwardly extending arm for pivoting said clock mechanism when said lugs engage said ratchet means, a spring loaded lever pivotally mounted adjacent said first clutch for disengaging said first clutch, a wire connected between said lever and said clock mechanism for pivoting said clock mechanism and disengaging said second clutch when said first clutch is disengaged, and means actuated by said lever for retaining said rack in the position it occupies when said lever is actuated.

7. In a well logging device the combination of a wire line connected to traveling blocks in a drilling rig, a pulley wheel around which said wire line passes, means for keeping said wire line tight around said pulley, a gear wheel in axial alignment with said pulley, lugs projecting from the sides of said pulley and gear wheel which face each other, said lugs being engageable with each other for connecting said pulley and gear wheel, a rotatable shaft in axial alignment with said pulley and gear wheel, a first clutch on said shaft engageable with said gear wheel for coupling said shaft to said gear wheel and having a groove therein, a disc on said shaft, two diametrically opposed lugs projecting from opposite sides of said disc, a ratchet support pivotally mounted adjacent said disc the free end of which is engaged by said lugs, a support supporting said ratchet support in a horizontal position, a dog on said ratchet support, a ratchet wheel shaft rotatably mounted above said ratchet support, a ratchet wheel on said ratchet wheel shaft engaged by said dog, a gear on said ratchet wheel shaft, a drilling rate recording drum rotatably mounted adjacent said ratchet wheel shaft having a gear wheel forming one end thereof, said gear meshed with said gear wheel on said drum, a pair of tracks parallel to theaxis of said drum and adjacent thereto, a rack having teeth on both sides thereof and of a length substantially equal to the length of said drum slidable on said tracks, a scriber mounted on said rack and contacting the surface of said drum, a stop on one of said tracks adjacent the end of said drum, a pulley between said tracks, a wire over said pulley having one end attached to said rack, a weight on the other end of said wire for urging said rack against said stop, an axle rotatably mounted beneath said tracks, a pinion on one end thereof engaged with said rack, a second clutch on the other end of said axle, a clock mechanism having a shaft axially aligned with said axle and connected to said second clutch for driving said rack at a constant rate of speed, said clock mechanism being pivoted for movement out of alignment with said axle for disengaging said second clutch, said clock having a downwardly extending arm thereon, a second disc on said shaft having a pair of diametrically opposed arms thereon engageable with said downwardly extending arm for pivoting said clock mechanism when said lugs engage said ratchet support and for disengaging said second clutch, a lever shaft rotatably mounted beneath said first clutch, a spring loaded lever pivotally mounted on said lever shaft and having a clutch engaging arm engaged in the groove of said first clutch, a wire connected between the free end of said lever and said clock mechanism for pivoting said clock mechanism and disengaging said second clutch when said first clutch is disengaged, a spring loaded bell crank between the ends of said pair of tracks opposite the pulley and having a point on the end of one arm thereof extending over said rack for engaging the teeth on the upper side of said rack and for holding said rack in a fixed position when said first clutch is disengaged, and a second wire connecting the other arm of said bell crank and said lever for operating said bell crank in response to the movement of said lever.

8. In a well logging device for use in connection with a drilling rig wherein a scriber is moved across a strip of record paper successive distances each corresponding to the elapsed time for a fixed increment of drilling distance and wherein said scriber is returned to its starting position following each successive time measurement for each successive drilling increment, the improvement which comprises a frame, a main shaft journalled in said frame, a pulley wheel rotatably mounted on said shaft, a cable passing over a portion of said wheel for driving the same, said cable being secured at one end to the traveling blocks of said drilling rig and being secured at the other end to a means for keeping said cable substantially taut, whereby, as said cable is payed out, said wheel is rotated an amount commensurate with the progress of the drilling operation, a clutch means for connecting said wheel to said shaft, means for moving said scriber from a fixed starting position across said paper at a constant rate of speed, means for urging said scriber in a direction opposite to the movement provided by said scriber moving means, means responsive to a predetermined angular movement of said main shaft for disengaging said scriber from said scriber moving means and for permitting said urging means to return said scriber to said starting position, a recording drum for receiving thereon said strip of paper, means responsive to said predetermined angular movement of said main shaft for rotating said drum intermittently and successively a predetermined angular amount, means for disengaging said clutch means, means connected between said clutch disengaging means and said scriber moving means for disengaging said scriber moving means when said clutch disengaging means is actuated, and means connected to said clutch disengaging means and engageable with said scriber when said clutch disengaging means is actuated for holding said scriber in the position occupied at the time that said clutch is disengaged.

9. A well logging device comprising a pulley wheel rotatable in response to the movement of the traveling blocks in a drilling rig, a shaft in the axial alignment with and disengageably coupled to said pulley wheel, a drilling rig recording drum rotatably mounted in said device, means responsive to the rotation of said shaft through a predetermined angular movement for intermittently rotating said drum successive and predetermined angular amounts, a scriber mounted adjacent said drum and contacting the surface of said drum, means for moving said scriber across said drum in a direction parallel to the rotary axis of said drum and at a constant rate of speed, means for urging said scriber in a direction opposite to the movement provided by said scriber moving means, means responsive to each successive predetermined angular movement of said shaft for disengaging said scriber moving means from said scriber and for permitting said urging means to return said scriber to its initial starting position, means for operatively disengaging said shaft from said pulley wheel, means connected between said shaft disengaging means and said scriber moving means for disconnecting said scriber moving means from said scriber when said shaft disengaging means is actuated, and means connected to said shaft disengaging means and engageable with said scriber when said shaft disengaging means is actuated for locking said scriber in the position it occupies at the time of actuation of said shaft disengaging means.

10. In a well logging device for use in connection with a drilling rig, a frame, a main shaft journaled in said frame, a pulley wheel rotatably mounted on said shaft, a cable passing over a portion of said wheel for driving the same, said cable being secured at one end to the traveling blocks of said drilling rig and being secured at the other end to a means for keeping said cable substantially taut, whereby, as said cable is payed out, said wheel is rotated an amount commensurate with the progress of the drilling operation, a clutch means for connecting said wheel to said shaft, a first scriber, a first rotatable drum journalled in said frame, means for moving said scriber across said drum at a contant predetermined rate of speed and in a direction parallel to the rotary axis of said first drum, means for urging said first scriber in a direction opposite to the movement provided by said scriber moving means, means responsive to a predetermined angular movement of said main shaft for disengagaing said first scriber from said scriber moving means and for permitting said urging means to return said scriber to its initial starting position, means responsive to said predetermined angular movement of saidmain shaft for rotating said first drum intermittently and successively a predetermined angular amount, means for disengaging said clutch means, means responsive to said clutch disengaging means for simultaneously disengaging said scriber moving means and for holding said scriber in a fixed position occupied by said scriber immediately prior to the disengagement of said clutch, a second drum rotatably mounted in said device, means for rotating said second drum at a constant angular speed, a second moveable scriber contacting the outer surface of said second drum and slidable in a direction parallel to the rotary axis of said second drum, and means for moving said scriber across said second drum at a rate commensurate with the rate of rotation of said pulley wheel.

References Cited in the file of this patent UNITED STATES PATENTS 2,357,051 McLaine Aug. 29, 1944 2,390,178 Rutherford Dec. 4, 1945 2,565,951 Crookston et al Aug. 28, 1951 2,600,336 Scivally June 10, 1952 2,628,498 Smith Feb. 17, 1953 2,679,161 Yancey- May 25, 1954 2,729,100 McCool et a1 Jan. 3, 1956 2,733,599 Storm Feb. 7, 1956