US2711880A

US2711880A - Pull down drive unit

Info

Publication number: US2711880A
Application number: US226619A
Authority: US
Inventors: Walter H Mckenzie
Original assignee: ARLEIGH R PATTERSON; EXPLORATION CONSULTANTS CORP; GEORGE W REED
Current assignee: ARLEIGH R PATTERSON; EXPLORATION CONSULTANTS Corp; GEORGE W REED
Priority date: 1951-05-16
Filing date: 1951-05-16
Publication date: 1955-06-28
Anticipated expiration: 1972-06-28

Description

J1me 1 MCKENZIE ,7M,8@

PULL DOWN DRIVE UNIT Filed May 16, 1951 2 Sheets-Sheet 1 INVENTOR. M H. M Kenzie June 2, 1955 Filed May 16, 1951 W. H. M KENZIE PULL DOWN DRIVE UNIT 2 Sheets-Sheet 2 JNVENTOR.

[ H. M Kenzie PULL DOWN DRIVE UNIT Walter H. McKenzie, Tulsa, Okla., assignor of one-fourth to George W. Reed, Tulsa, Okla., one-fourth to Arleigh R. Patterson, Wilson, kla., and one-fourth to Exploration Consultants Corporation, Tulsa, Okla., a corpora- .tion of Delaware Application May 16, 1951,'Serial No. 226,619

4.Claims. (Cl. 255-22 This invention relates to a method of and apparatus for automatically imposing a constant weight on the drill bit of a portable drilling unit.

As it is well known, in. using a-portable drilling unit the bore holes drilled are usually relatively shallow; therefore, the weight of the Kelly bar and drill pipe is frequently insuflicient to press the drill bit downward and provide the desired penetration. It is .then necessary to place additional weight on the drill bit. This is usually accomplished by .imposing aportion of the weight of the truck and drilling rig upon the Kelly bar by'the use of pull down chains. The chains are suitably connected to the top of the Kelly bar and are driven by a power take-off from the truck engine through the medium of suitable gearing and a manually operated clutch. The pull down chains are operated as desired by engaging and disengaging the manually operated clutch. In applying weight to the drill bit in this manner, the driller must pay constant attention to the drilling operation to operate the clutch and apply and remove weight from the drill bit to preclude overloading or underloading the drill bit.

The present invention contemplates a novel method of and apparatus for imposing a constant weight on the drill bit of a portable drilling unit during the entire vertical travel of the Kelly bar made for'each joint of drill pipe used in the drilling operation. The pull down chains are driven until the rear portion of the truck is raised a predetermined degree to impose the weight of the truck on the Kelly bar. The pull down chains are then driven in accordance with the downward movement of the Kelly bar to retain the truck in a predetermined tilted position, thereby maintaining a uniform weight on the Kelly bar and drill bit. As one embodiment, it is contemplated to drive the pull down chains by an electric motor through the medium of a transmission unit. The electric motor is cont'rolledby a spring urged switchadapted to be automatically operated by a stationary control rod in accordance with the height of the truck.

An important object of this invention is to provide a z novel method and means for imposing a constant weight on the drill bit of a portable drilling unit.

Another object of this invention is to increase the efiiciency of portable drilling units.

A further object of thi's invention is to provide an automatic drive for the pull down shaft of a portable drilling unit.

' A still further object of this invention is to provide an eflicient pull down drive means which may be economically manufactured,

Other objects and advantages of the'invention will be evident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate my invention.

In the drawings:

Figure 1 is a schematic rear elevational view of a portable drilling unit.

ice

Figure'2 is a plan view of the drilling unit shown in Fig. 1 with the rig structure removed.

Figure 3 is a wiring diagram of the electrical circuit utilized in one embodiment of the present invention.

Figure 4 is a cross-sectional view taken on lines 44 of Figure 2.

Referring to the drawings in detail, and particularly Fig. 1, reference character 2 designates the bed portion of a truck supported by a pair of wheels 4 through the medium of an axle (not shown), axle housing 6 and springs 7. A rig structure 8 is mounted on the rear portion of the truck bed 2 and has a pair of sheaves 10 rotatably supported in the upper portion thereof. A rotary table 12 is rotatably supported on the truck bed 2 and is adapted to be driven by suitable machinery (not shown) in the usual manner. Telescopically disposed in the rotary table 12 is a Kelly bar 14 for transmitting the rotary motion of the table 12 to the drill pipe and drill bit (not shown). A plurality of joints of drill pipe (not shown) with a drill bit on the lower end thereof, are secured in tandem relation to the lower end of the Kelly bar 14 in a manner well known in the art. A suitable swivel 16 is provided on the upper end 18 of the Kelly bar 14 and has a pair of arms 20', usually termed heavener bars, extending from opposite sides thereof. The swivel 16 permits rotation of the Kelly bar 14 independent of the heavener bars 20. A conduit 22 extends upwardly from the Kelly bar 14 and is utilized to supply drilling fluid to the drill bit in the usual manner.

A pair of chains 24 are suitably secured to the heavener bars 20 and extend downwardly around sprockets 26 mounted on a pull-down shaft 28 extending transversely across the truck bed 2. The shaft 28 is rotatably supported on the truck bed 2 by pillow block type bearings 30. The chains 24 extend upwardly from the respective sprockets 26 and are connected at the opposite ends to cables or wire lines 32. The cables 32 extend upwardly over the sheaves 10, and then downwardly for connection with the heavener bars 20.

An additional sprocket 34 is secured on the pull-down shaft 28 and is interconnected by a chain 36 (see also Fig. 2) to a sprocket 38 rigidly mounted on another transversely disposed shaft 40. One end 42 of the shaft 40 is rotatably supported by a pillow block type bearing 44 on the truck bed 2, and the opposite end 46 thereof extends into a suitable gear box 48. The shaft 40 is adapted to be driven, through gears (not shown) in the gear box 48, by a shaft 50 connected to a power take-off (not shown) of the truck engine (not shown). The gears (not shown) in the box 43 may be any suitable compound gears usually found in "gear boxes for conventional winches, for example, one

small and one large gear forming compound gears. A suitable clutch 52 is interposed in the shaft 40 to control operation of the sprocket 38.

Ordinarily, when it is desired to place weight on the Kelly bar 14 and hence the drill bit, the driller operates the clutch 52 to cause engagement thereof. Assuming the drive shaft 50 is being rotated by the truck engine, the shaft 40 will then be rotated to drive the sprocket 38. The sprocket 38 drives the sprocket 34, pull-down shaft 28 and sprockets 26 through the medium of the chain 36. It is readily seen that the movement of the I sprockets 26 is transmitted through the chains 24 (Fig. 1)

and heavener bars 20 to the Kelly bar 14 to move the Kelly bar 14 in a downward direction through the rotary table 12.

In the event the drill bit is operating in a hard formation, the Kelly bar 14 will not move downward as fast as the chains 24 are pulled by the sprockets 26. Therefore, the chains 24 will pull upwardly on the sprockets 26 and pull-down shaft 28. Since the pull-down shaft 28 is secured to the truck bed 2 by the bearing units 30, the truck bed 2 will thereby be raised or tilted to impose a portion of the weight of the truck bed 2 on the Kelly bar 14 and drill bit. When the truck bed 2 has been raised to the desired height, the clutch 52 is disengaged. As the drill bit penetrates the formation, the Kelly bar 14 and truck bed 2 move downward, with a consequent decrease in the application of weight on the drill bit. Obviously, the higher the truck bed 2 is raised or tilted, the greater will be the application of weight on the drill bit.

The present invention contemplates an automatic drive for the pull-down shaft 28 to retain a constant weight on the Kelly bar 14. As one embodiment, I provide a sprocket 54 (Fig. 2) on the shaft adjacent the sprocket 38. The sprocket 54 is interconnected by a chain 56 to a sprocket 58 disposed on the output shaft 60 of a suitable transmission 62. The transmission 62 is of the usual type, having forward and reverse gears (not shown) as well as a neutral position. Furthermore, the transmission 62 is secured to the truck bed 2 in any suitable manner (not shown). Another sprocket 64 is secured on the input shaft 66 of the transmission 62. The sprocket 64 is interconnected by a chain 68 to a complementary sprocket 70 provided on the drive shaft 72 of an electric motor 74.

A suitable storage battery 76 provides a source of electrical energy for the motor 74, and is connected thereto by an electric circuit shown diagrammatically in Fig. 3. One side of the battery 76 is grounded by a wire 78, and the opposite side thereof is interconnected by a wire 80 to the motor 74, with suitable switches interposed therebetween, and a suitable fuse 82 is interposed in the wire 80 to preclude an overloading of the circuit in the usual manner. Connected in series with the fuse 82, and between the battery 76 and motor 74, is a single pole, single throw switch 84; in turn connected with a single pole single throw switch 86 of the push button type, normally closed and having a spring return; and cooperating with a time delay relay 88; and a solenoid relay all interposed in the wire 80. A short circuiting wire 92 is interconnected to the wire 80 between the switches 84 and 86, and between the time delay relay 88 and the solenoid relay 90 to short circuit the switch 86 and relay 88 as will be more fully hereinafter set forth. A suitable switch 89 may cooperate with the relay 90 to provide electric communication between the battery 76 and the motor 74 in any suitable manner. is interposed in the wire 92 and is normally in an open position to preclude the flow of the current through the wire 92. The motor 74 is grounded by a wire 26 in a well known manner. It will be apparent that the motor 74 receives electric current directly through the switch 89 upon actuation thereof by the relay 90.

Referring again to Fig. 2, a suitable switch box 98 is mounted on the rear portion of the truck bed 2 convenient to the driller. Another switch box 100 is mounted on the truck bed 2 forward of the switch box 98 and directly above the axle housing 6 of the truck. The switch box 100 is adapted to contain the fuse 82, switch 86, time delay relay 88, and solenoid relay 90. The push button 102 of the switch 86 extends above the switch box 100 as clearly shown in Fig. 4. A vertical control rod 104 is secured at its lower end to the axle housing 6 and extends upwardly through an aperture 106 provided in the truck bed 2 adjacent the switch box 100. A transverse arm 108 is provided on the upper end of the control rod 104 in such a position to extend directly over the push button 102. The length of the control rod 104 is preferably adjustable (not A single pole single throw switch 84 Iii) shown) to vary the height of the arm 108 for purposes as will be hereinafter set forth.

Suitable conduits 110 (Fig. 2) interconnect the motor 4 74, battery 76 and

switch boxes

98 and 100 to carry the electrical wiring 80 and 92'fin the usual manner.

Operation In utilizing the present pull-down drive, the clutch 52 is disengaged to permit operation of the shaft 40 independent of the operation of the drive shaft 50. To place the drive in operation, the driller simply closes the switch 84 which is located in the switch box 98. Since the switch 94 is normally open and the switch 86 is normally closed, current will flow from the battery '76 through the wire 80 to operate the motor 74. The motor 74 in turn drives the transmission unit 62 through the medium of

sprockets

70 and 64 and chain 68. Assuming the transmission 62 is set to drive in a forward direction, the sprockets 58 will be rotated in the same direction as the sprockets 64 to drive the sprockets 54, shaft 40 and sprocket 38 through the medium of chain 56. The chain 36 will therefore be driven to drive the pull-down chains 24 and place a downward pull on the Kelly bar 14 in the same manner as previously set forth.

In the event the drill bit is drilling in a hard formation and the Kelly bar 14 will not move down at a suificient rate of speed, the pull-down chains 24 will exert an upward pull on the truck bed 2 through the medium of the sprockets 26, shaft 28 and bearing units 30. The rear portion of the truck bed 2 will thereby be raised to tilt the truck in a forward direction and impose a portion of the load of the truck on the Kelly bar 14 and drill bit. The large and small compound gears (not shown) provided in the gear box 48 prevents any unwinding of the pull down chains 24. As his well known, the truck springs 7 will permit a variable amount of upward movement of the truck bed 2 independent of the axle housing 6 and wheels 4. Therefore, as the truck bed 2 is raised or tilted by the pull-down chains 24, the push button 102 (Fig. 4-) will be moved upwardly toward the arm 108 of the stationary control rod 104. The arm 108 will thereby, in effect, depress the push button 102 when the truck bed 2 has been raised a predetermined degree to open the switch 86 and disrupt the supply of electrical energy to the motor 74;. The motor 74 will then become inoperative and stop further movement of the pull-down chains 24. The chains 24, being secured at one end to the heavener bars 20 and secured at their opposite ends to the cables 32 which are in turn secured to the heavener bars 20, will retain the truck bed 2 in a fixed position relative to the Kelly bar 14.

As the drill bit penetrates the formation, the Kelly bar 14 and truck bed 2 will move simultaneously in a downward direction. The push button 102 will thereby be moved downward away from the arm 108. Since the switch 86 is of the spring return type, the push button 102 will be automatically raised when released by the arm 108 to close the switch 86 and again permit a fiow of electrical energy to the motor 74. The motor 74 will then again drive the pull-down chains 24 and raise the truck bed 2 until the push button 102 is actuated by the I arm 108.

0 stant weight is retained on the drill bit. The time delay relay 88 may be set to operate atany desired speed, and is utilized to reduce vibrations in the truck bed 2 due to the frequent operations of the switch 86. I

When the Kelly bar 14 has been moved downward the desired degree, the transmission unit 62'is placed in reverse to drive the pull-down chains 24 in an opposite direction and raise the Kelly bar 14 through the medium of the cables 32 and heavener bars 20. An additional joint (not shown) of drill pipe may then be secured to the Kelly bar 14 and the drilling operation repeated. The switch 94 may be closed when the transmission 62 is placed in reverse to short circuit the switch 86 and time delay relay 88 and expedite the raising of the Kelly bar 14. Furthermore, the switch 94 may be utilized during the drilling operation in the event the switch 86 or time delay relay 88 become inoperative. The operation of the pull-down chains 24 will then be manually controlled by the driller.

From the foregoing, it is apparent that the present invention provides a novel method of and apparatus for imposing a constant weight on the drill bit of a portable drilling unit. The truck on which the unit is mounted is tilted a predetermined degree with a portion of the truck weight imposed on the Kelly bar, and is retained in a predetermined tilted position, to impose a constant weight on the drill bit. The drive for the pull-down shaft is fully automatic to materially increase the efficiency of the entire drilling unit. It is also apparent that the present invention provides an efficient drive means that may be economically manufactured.

Changes may be made in the combination and arrangement of parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

I claim:

1. A pull-down drive for a drilling apparatus disposed on a truck and including a Kelly bar, pull-down chains for tilting the truck and imposing the weight of the truck on the Kelly bar, an electric motor for driving the pulldown chains to cause a tilting of the truck, a source of electrical energy, transmitting means for transmitting electrical energy from said source to the motor, and means for automatically connecting and disconnecting said transmitting means in accordance with the tilt of the truck, to provide an essentially constant angle of tilt of the truck and uniform weight on the Kelly bar during operation of the drilling apparatus.

2. A pull down drive for a drilling apparatus having a Kelly bar and mounted on a truck, pull down chains for tilting the truck and imposing the weight of the truck on the Kelly bar, an electric motor drivingly connected to the pull down chains to cause the tilting of the truck, a source of electrical energy, an electrical circuit interconnecting the motor and said source for energizing the motor, a switch in the electrical circuit, stationary means carried by the truck, said switch being responsive to the angle of tilt of the truck for alternate engagement and disengagement with the stationary means to maintain the truck at a substantially uniform angle of tilt and impose a uniform weight on the Kelly bar during operation of the drilling apparatus.

3. A pull down drive for a drilling apparatus having a rotatable Kelly and mounted on a truck, pull down chains mounted on the truck, a power unit for driving the pull down chains providing for a tilting of the truck and imposing the weight of the truck on the Kelly, a source of energy for the power unit, means for supplying energy from said source to the power unit, control means carried by the truck and connected to said supply means normally providing a flow of energy to the power unit for operation of the pull down chains, rod means carried by the truck for cooperation with the control means, said control means being responsive to the tilt of the truck and adapted to engage the rod means whereby the supply of energy to said power unit is caused to be disrupted.

4. An automatic pull down drive for a drilling apparatus having a rotatable Kelly bar, pull down chains mounted on the truck, an electric motor for driving the pull down chains to provide for tilting and imposing the weight of the truck on the Kelly bar, a source of electrical energy, a circuit connecting said source to the motor, a spring urged switch interposed in the circuit and normally in closed position to provide for a flow of energy to the motor, a stationary rod carried by the truck, switch means carried by the truck and responsive to a predetermined tilted position of the truck to engage the rod to cause a disruption of the flow of energy to the motor, and a time delay relay in the circuit for delaying operation of the switch and dampening vibration of the truck,

References Cited in the file of this patent UNITED STATES PATENTS 2,005,122 Young et al June 18, 1935 2,080,804 Brantly May 18, 1937 2,128,650 Knoerzer Aug. 30, 1938 2,458,241 Beck Jan. 4, 1949 2,516,182 Bury July 25, 1950 2,594,098 Vanderzee Apr. 22, 1952