US2873950A

US2873950A - Spring loaded earth drill

Info

Publication number: US2873950A
Application number: US406030A
Authority: US
Inventors: Charles W Kandle
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-01-25
Filing date: 1954-01-25
Publication date: 1959-02-17
Anticipated expiration: 1976-02-17

Description

Feb. 17, 1959 v c. w. KANDLE 2,873,950

I SPRING LOADED EARTH DRILL Filed Jan. 25, 1954 v I 2 Sheets-Sheet l W W! FIG.1.- um 5 IN VEN TOR. C hqrles W. Kcmd Ze ATTORNEYS Feb. 17, 1959 c. w. KANDLE SPRING LOADED EARTH DRILL 2 Sheets-Sheet ATTORNEYS.

INVENTOR. Charles W. Kanclle x jauz Filed Jan, 25. 1954 United States Patent SPRING LOADED EARTH-- DRILL Charles W. Kamlle, Chicago, 11].,

Application January 25, 1954,.Serial.No'. 406,030

6 Claims. (Cl.255.--4.8);

This inventionrelatesto earth drills. of relatively large diameterandparticularly to rotated bucket drills which fill while drillingand are periodically Withdrawn from the hole and dumped.v

Theinventionallowsv operating the drill by amotor associated therewith and provides for the downward pressure of the drill while allowing means to. be extended to engage the sidewalls of the hole and secure the motor against rotation by torque reaction.

An object of the invention is'to provide for-the positive downward feed of the drill utilizing the weight of the motor associated with the drill as a unit while securing-the motor against torque reaction and vertical movement;

The drawings "furnished.herewithyillustrate the best mode of carrying 'out the invention as presently conteifiplated and set forth hereinafterr In the drawings:

Figured is a perspectiveyview of the bucket drill with the upper cutters withdrawn and the lower end of the bucket opened for dumping the contents of the same; Fig.2 is a vertical crosssection of part of the drill and shows other parts including the motor and rigging in elevation with the unit lowered in the earth and in the process of continuing the drilling operation;

Fig. is a sectiontaken ou line 3- -3 of Fig, 2 and includes a top plan view of the drillin the earth;

2 Fig.4 is an'enlarged-elevation of a part ofthe drive "shaft showing the drive rollers accomrnodating the axial movement of the shaft relative to the drill; and

Fig.--5 is an enlarged'section taken on line 5-5 of Fig. 2.

p The drill shown inthe drawings lIlCllldCS 'th cylinder land the lower plate 2. Plate 2 forming the head of the drill isprovided with the lead screw' Sand is secured at the lower end of cylinder 1 bythehinge 4 and the latch 5. The cutters -6 fixed to plate'2 are set in the leading edge of each of the twosector openings 7 formed in the-plate The two oppositely disposed upper cutting arms 8 extendradially-beyond the outer dimensions of cylinder 1. The inner end of the arms 8 are secured by the' bolts 9 to the underside of the cross-head 10 welded'to extend across the upper end of cylinder 1.

The upper rim ofcylinder 1 isrecessed as at 10a to allow the cutters to swing on bolts 9 for pivotal movement from a retracted position as shown in Figure l to an outer extended position as shown-in Fig. 2. In the extended position each cutter arm 8 abuts the crosshead and is securedin that position by rotation of the drill in the forward direction. Arms 8 may be moved initially toward extended position by centrifugal action, and thereafter their engagement with the dirt will force thenrto the extended stop position. The cutters will remain in extended position during drilling, and until the direction of rotation of the drill is reversed. Each cutter arm Sis provided with a sharp leading edguewhich exice tends outwardly and upwardly from the upper rimof cylinder 1 and isprovided with-the deflector plates; 11 which extend upwardly from the rear side of each cutter and forwardly thereof to direct the spoil cut away from the earth intothe upper part of the cylinder andload the same.

In operation, the rotation of the drill and the action of

cutters

6 and 8 loads the drill both from the bottom and the top. The spoil from cutters 6 in advance of the cylinder 1 and. plate 2 fills the drill through openings 7. Cutters 8 forma 'frusto-conical face between the smalleryhole corresponding to the diameter of cylinder 1 and the larger bore defined by cutters 8. The projecting cutters 12 adapted to engage the abutments 13 project outwardly from the lower :edge -ofplate 2 and serve to enlarge, the opening "-forcylinder-l and reduce the resistance of frictional contact of the cylinder with/the sidewall 'oftthesmaller bore:

Upon filling the bucket, the rotation of the drill is reversed momentarily which causes-

cutters

8 and 12 to be retracted by pivoting in a reverse direction; and the drill, is then lifted from the hole. When moved away from the hole the lower plate 2 is unlatched and swings downwardly to open the cylinder and release the contents.

The motor 14 driving the drill is suspended by'the cable 15 and includes a shaft which fits the upper drive collarld of the drill. The removable pins 17-inserted through the drive collar 16 and motor shaft providefor the drive "connection of the drill and motor and the supportof the cross-bar '18, fixed to collar 16. Chains 19'connecting barr18 and cross=head 10 provide for the support of the drill as in lifting the motorby the cable 15,.

The rotation of the drill is provided by thegsquare shaft 20 extending from collar 16 into the square, broached bore 21 of the tube 22carried in cross-head 10. Shaft 20 is fitted with the rollers 23v in the recesses 24- of the shaft, to project therefrom andvengage the corresponding walls of hole 21. Rollers 23 are fitted with the sleeve bearings 25 and are mounted in pairs on corresponding pins 26 which extend across the shaft and through the recesses; Rollers 23 provide for the axial movement of shaft 20 in tube 22 with nominal frictional resistance while providing the transmission of torque from motor "14 to the drillvto drive the latter.

Rotation of the shaft of motor 14 is imparted through square shaft 20 and tube 22 to cylinder 1, rotation of the latter providing rotation of lead screw? and cutters 12 for drilling, togetherwith cutters 8.

The lower end of tube 22 is closed and the fiexbile sleeve 27 extending frorrrthe upper end of the tube to cross-bar 18 is preferably provided, as shown in Figure 2, to close the upper end of the tube and enclose the spring 28 mounted on shaft 24] between cross-head 10 and cross-bar 18. Spring 28 is of a capacity slightly less than the weight of motor 14 so that upon lowering the motor and drill to the ground the weight of-the motor when unsupported will'compress spring 28 until the shaft is fully retracted in tube 22.

Suitable means for handling the motor and drill as the rigging 29 and winch 30 may be provided for raising and lowering of the motor and drill. In starting the drilling of a hole with plate 2 fiat on the ground, the motor 14 is secured against rotation by suitable bracing, not shown, and cable 15 is slacked so that the motor lowers and compresses spring 28. Cable 15 may be here employed to maintain the drill upright if necessary.

After drilling to a depth where the motoris level with the ground and the bracing referred 'to cannot follow the motor into the hole, the motor, while-stillsecured by said bracing, is then supported by cable 15 and the drilling continued with only the drill moving downwardly by spring 28 to a depth where the drill is supported by the chains 19.

At that depth the bracing referred to may be dispensed with and the motor lowered to again compress spring 28. The motor 14 will then be in the ground sufficiently to allow securement of the motor against turning by the hydraulically actuated cylinders 31 secured to the motor.

Cylinders 31 extend horizontally in opposite directions and each is fitted with a piston 32 and the piston rod 33 which carries the track shoe 34 at the outer end thereof. Shoes 34 are movable outwardly by fluid pressure supplied to cylinders 31 through the lines 35 connected thereto, and are engageable directly with the sides of the hole or with the vertical tracks 36 placed in the hole to engage the sides thereof. Each track 36 may be suspended from rigging 29 or from other anchorage, not shown, provided at ground level.

Retraction of shoes 34 to permit removal of the drill unit from the hole for dumping the accumulated spoil is effected by fluid pressure supplied to cylinders 31 through lines 37 disposed on the opposite sides of the respective pistons 32 from lines 35.

The pressure system shown diagrammatically in Fig. 2 may be utilized to supply the pressure fluid to the opposite sides of the respective pistons 32 to alternately move shoes 34 outwardly and inwardly. The system includes a supply tank 38 of hydraulic fluid and a pump 39 connected thereto for developing the pressure desired. From pump 39 the fluid is moved through a pressure line 40 and through a two-position valve 41 which is adapted to direct the pressure fluid to either '7 line or line 37. In the position of valve 41, as shown, the pressure fluid is being directed through line 35 and line 37 serves as a return line for the hydraulic fluid. Suitable passages in valve 41 direct the returning fluid from line 37 to the return line 42 which empties into the supply tank 38. In the second position of valve 41, the pressure fluid is directed through line 37. In this position line 35 serves as the return line for the hydraulic fluid and communicates with return line 42 through suitable passages in valve 41. V

In the operation of the drill when motor 14 is below the ground level, the engagement of shoes 34 with tracks 36 provides securement of the motor against torque reaction. Such securement generally requires considerable force exerted against the walls by the cylinders 31 because of the size of the hole being drilled, and generally does not allow downward sliding of the shoes on the track without elaborate Wheels or the like which are exposed and subject to clogging and freezing.

According to the invention, vertical movement may be afforded the drill by providing relative movement of the drill and motor and with the spring 28 providing the downward pressure which would otherwise be provided by the weight of the motor. It has been found that the limited relative vertical movement afforded between the motor and drill is generally more than adequate for the forward feed of the drill in the course of one filling of cylinder 1. That is, with a reasonable length of shaft 20 and tube 22, the limit of movement allowed by chains 19 will not ordinarily be reached before the cylinder 1 is filled and the drill and motor unit must be raised and emptied anyway.

In addition to limiting relative movement of shaft 20 and tube 22, which might be provided by other abutment means, chains 19 serve with unique simplicity and complete reliability as a guide to the operator of the relative positions of the motor and drill. In most usual operations the shoes 34 may engage the side walls of the hole directly. The shoes should be of a size to provide the necessary footing to securethe motor against torque reaction. However, in more severe conditions, the shoes would have to be too large to be adequate.

In such cases the tracks 36, as shown, provide the foota casing would extend down to the shoes 34 with the lowermost section having fittings adapted to be engaged by the shoes.

Various modes of carrying out the invention are contemplated as within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

1 claim:

1. In an earth drill unit adapted to receive and contain the spoil for periodic removal from a hole being drilled, a cylinder, a plate removably secured to the lower end of the cylinder and having segmental openings fitted with cutters for drilling in advance of the cylinder and directing the spoil through the openings into the cylinder, a motor unit disposed above the cylinder, means connecting the motor and cylinder to provide rotation of the latter, means associated with said connecting means to permit limited relative axial movement between said motor and cylinder in a vertical direction, extensible arms connected to the motor and adapted to engage the sides of the hole to secure the motor against rotation by torque reaction and against vertical movement, means to extend said arms into engagement with the sides of the hole, and a spring associated with said connecting means and disposed between said motor and cylinder, said spring being com pressible by the weight of the motor, said drillunit being adapted to be lowered into the hole to be drilled and said arms being adapted to be extended into engagement with the earth after the cylinder reaches the bottom of the hole and the motor is moved downwardly to compress the spring whereby the spring provides substantially the equivalent of the weight of the motor for the downward feed of the drill while the motor is supported vertically and rotationally by said extensible arms.

2. The invention of claim 1 wherein the connecting means comprises an extensible shaft assembly including a rotatable drive shaft member extending from the motor unit, a driven tubular member connected to the cylinder and having a bore adapted to receive the drive shaft member for rotation therewith and being movable ax ially relative thereto, and rollers mounted on one of said members in rolling engagement with the other of said members to permit the free lowering of the cylinder during the operation of the drill.

. 3. In an earth drill unitadapted to receive and contain the spoil for periodic removal from a hole being drilled, a cylinder, a plate removably secured to the lower end of the cylinder and having segmental openings fitted with cutters for drilling a hole substantially equal to the diameter of the cylinder and directing the spoil through the openings into the cylinder, a motor unit disposed above the cylinder, extensible shaft means connecting the motor and cylinder and permitting limited relative axial movement between the motor and cylinder in a vertical direction, lateral arms connected to the motor and adapted to engage the sides of the hole to secure the motor against rotation by torque reaction and against vertical movement, means to extend said arms into engagement with the sides of the hole, a spring disposed between said motor and said cylinder and providing biasing of said shaft means to extend the same, said spring being compressible by the weight of the motor, and means secured to the axiallymovable por-' said arms adapted to be extended into engagement with the earth upon movement of the motor downwardly and upon compression of the spring by weight of the motor whereby the spring provides substantially the equivalent of the weight of the motor for the downward feed of the drill while the motor is supported vertically and rotationally by said arms.

4. The invention of claim 3 wherein the movement limiting means comprises means to provide a general visual indication of the relative positions of the motor and cylinder.

5. In an earth drill unit adapted to receive and contain the spoil for periodic removal from a hole being drilled, a cylinder having upper and lower open ends, a circular plate having segmental openings and being otherwise adapted to close the lower end of said cylinder, means securing said plate to the lower end of said cylinder and adapted to be released to allow the plate to swing downwardly and release the contents of the cylinder, cutting teeth carried by said plate within said openings and adapted to remove the earth in advance of the plate upon rotation thereof with the cylinder and to deliver the spoil upwardly through the openings thereof into the cylinder' to fill the latter, a cross-member fixed to the upper end of the cylinder, opposite cutting arms pivotally secured to said cross member and adapted to extend radially outwardly of the cylinder to enlarge the hole, each arm having an upwardly extending frustoconical face for deflecting the spoil into the upper open end of cylinder, a tube carried by said cross-member concentrically of the cylinder, a drive shaft fitting said tube and having a series of rollers engaging the inner walls of said tube to permit the axial movement of the shaft within the tube, a cross-arm fixed to the upper end of said shaft, a spring mounted on said shaft between said cross-member and cross-arm, extensible connecting members disposed between the cross-member and crossarm to limit the relative movement of said shaft within the tube and permit a preloading of said spring, a drive motor having a drive shaft connected to the upper end of said first-named shaft above the cross-arm to rotate the drill in either direction, the bore of said tube permitting transmission of torque by said first-named shaft and said rollers between said motor and said cylinder, a pair of extensible arms connected to and extending from said motor and adapted to engage the side wall of the enlarged hole formed by said radial cutting arms, means to extend said arms into engagement with the side walls of the hole to support said motor against vertical and rotational movement, the preloading of said spring being less than the weight of said motor whereby the motor when unsupported compresses the spring, the compression of said spring providing substantially the equivalent of the weight of the motor for the downward feed of the drill while the motor is supported vertically and rotationally by said arms, said cuttting arms being retractable upon the reverse rotation of the drill to alllow for withdrawal of the unit from the hole and the dumping of the contents of the cylinder.

6. In an earth drill unit adapted to receive and contain the spoil for periodic removal from a hole being drilled, a cylinder having upper and lower open ends, a circular plate having segmental openings and being otherwise adapted to close the lower end of said cylinder, hinge means and a latch securing said plate to the lower end of said cylinder, said latch being adapted to be released to allow the plate to swing downwardly and release the contents of the cylinder, cutting teeth carried by said plate within said openings and adapted to remove the earth in advance of the plate upon forward rotation thereof with the cylinder and to deliver the spoil upwardly through the openings thereof into the cylinder to fill the latter, lower radial cutters pivotally secured to the lower face of said plate and projecting beyond the radial dimentions of the cylinder for the rotation thereof with a minimum of frictional resistance, a cross-member fixed to the upper end of the cylinder, opposite cutting arms pivotally secured to said cross-member and adapted to extend radially outwardly of the cylinder to enlarge the hole, each arm having an upwardly extending frusto-conical face for deflecting the spoil into the upper open end of the cylinder, a tube carried by said cross-member concentrically of the cylinder, a drive shaft fitting said tube and having a series of rollers engaging the inner walls of said tube to permit the axial movement of the shaft within the tube, a cross-arm fixed to the upper end of said shaft, a spring mounted on said shaft between said cross-member and cross-arm, a plurality of chains connecting said arm and the cross-member and limiting the relative movement of said shaft within the tube to permit a preloading of said spring, a drive motor having a drive shaft connected to the upper end of said first-named shaft above the cross-arm to rotate the drill in either direction, the bore of said tube permitting transmission of torque by said first-named shaft and said rollers between said motor and said cylinder, a pair of extensible arms connected to and extending from said motor and having outer shoes adapted to engage the side wall of the enlarged hole formed by said radial cutting arms, means to extend said arms to place said shoes into engagement with the side walls of the hole to support said motor against vertical and rotational movement, the preloading of said spring being less than the weight of said motor when unsupported compresses the spring, the compression of said spring providing substantially the equivalent of the weight of the motor for the downward feed of the drill While the motor is supported vertically and rotationally 'by said arms, said radial cutters and cutting arms being retractable upon the reverse rotation of the drill to allow for withdrawal of the unit from the hole and the dumping of the contents of the cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 463,880 Webber Nov. 24, 1901 2,091,779 Gooder Aug. 31, 1937 2,631,013 Darin Mar. 10, 1953