US3185226A

US3185226A - Shaft sinking apparatus

Info

Publication number: US3185226A
Application number: US800000A
Authority: US
Inventors: Robbins Richard James
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-03-17
Filing date: 1959-03-17
Publication date: 1965-05-25
Anticipated expiration: 1982-05-25

Description

y 25, 1965 R. J. ROBBINS 3,185,226

SHAFT S INKING APPARATUS Filed March 17, 1959 7 Sheets-Sheet l INVENTOR May 25, 1965 R. J. ROBBINS SHAFT SINKING APPARATUS 7 Sheets-Sheet 2 Filed March 17, 1959 INVENTOR. Rama .I EaZZl'M May 25, 1965 R. J. ROBBINS SHAFT SINKING APPARATUS 7 Sheets-Sheet 5 Filed March 17, 1959 May 25, 1965 R. J. ROBBINS 3,185,226

SHAFT SINKING APPARATUS Filed March 17, 1959 7 Sheets Sheet 4 IN V EN TOR.

y 5, 1965 R. J. ROBBINS 3,185,226

SHAFT SINKING APPARATUS Filed March 17, 1959 7 Sheets-Sheet 6 22 IN V EN TOR.

A NEY May 25, 1965 R. J. ROBBINS SHAFT SINKING APPARATUS 7 Sheets-Sheet '7 Filed March 17, 1959 Mme/q United States Patent 3,185,226 SHAFT SINKING APPARATUS Richard James Robbins, 321 Grosvenor House, Seattle, Wash. Filed Mar. 17, 195?, Ser. No. 8%,098 Cim'ms. (Cl. 175-102) This invention relates generally to mining and more particularly to an improved apparatus for excavating large diameter holes.

In the known methods and apparatus, for sinking mine shafts or the like, it is usually necessary to have available some type of entry or drift at a lower level which is connected to an adjacent existing shaft or other entry which enables the cuttings material which is excavated in sinking the proposed mine shaft to be removed generally downwardly through the lower level to the adjacent existing shaft or entry and then raised or taken to the surface. Another common method of excavating a mine shaft is to raise the proposed shaft from the lower existing level, drift or entry to the ground surface.

In shaft sinking operations wherein there is no existing lower level, drift or entry and the proposed mine shaft is to be excavated by advancing the mine shaft bottom to a dead, great dificulty is had since the excavation and removal of the cuttings material generally take place in the same location.

It is the principal object of this invention to provide an improved apparatus for excavating a generally vertical hole having a diameter of at least approximately feet.

It is an object of this invention to provide an improved apparatus for sinking generally vertical mine shafts, or the like.

It is an additional object of this invention to provide an improved apparatus for excavating holes in the ground which includes a flushing water head to facilitate in the removal of cuttings material from the hole.

Another object of this invention is to provide an improved apparatus for sinking a mine shaft, or the like, wherein the mine shaft is advanced to a dead.

A further object of this invention is to provide an improved apparatus for excavating a hole in the ground wherein a pilot hole is first excavated and then expanded substantially continuously from one end to the other with the advancement of the pilot hole and the expansion thereof being generally in the same direction.

A still further object of this invention is to provide an improved apparatus for sinking a mine shaft, or the like, which is economical in cost, efficient in operation and reliable in use since there is a large saving of both costs and lapsed time in using the improved method and apparatus.

A still further additional object of this invention is to provide an improved apparatus for sinking large diameter mine shafts, or the like, wherein an even, regular surface is left by the excavating action of the apparatus in comparison with such surface as normally left by blasting. Further, the mine shaft surface left by the apparatus in accordance with this invention is not shattered, cracked or weakened as in the case of normally excavating the surface by blasting.

In order to overcome the disadvantages and objections to known and common methods and apparatus for excavating mine shafts, or the like, and in order to accomplish the desired objects as stated above, the improved apparatus for excavating large diameter holes in the ground in accordance with this invention contemplates first, excavating a pilot hole either to the desired depth of the proposed shaft so that the pilot hole extends substantially the entire distance or at least to a depth sufiicient to define a loading zone skip pocket, and then plac- "ice ing a casing within the pilot hole with the casing being provided with a plurality of generally peripherally spaced openings. The casing extends above ground surface and defines an unloading zone or a skip dump and a skipway shaft and a skip is positioned within the casing and suitable hoisting means is provided for hoisting the skip through the casing to ground surface. The material which is generally outwardly disposed relative to the casing is then removed by a suitable cutting and/ or conveying apparatus while maintaining the pilot hole in advance of the shaft working face with the cuttings material which is removed by the cutting and/ or conveying apparatus being passed through the openings in the casing into the skip and then hoisted to the surface. The improved method and apparatus enables a mine shaft, or the like, to be sunk to a dead by first excavating material to establish the pilot hole by advancing the pilot hole in a given direction and then effectively expanding the pilot hole by excavating the material which is outwardly positioned immediately adjacent the pilot hole with the advance of the expansion being in substantially the same direction as the advance of the pilot hole. By maintaining the pilot hole beyond the shaft working face a given distance, it is possible that the skip may be positioned within the advanced portion of the pilot hole, which defines a skip pocket, so that the material may then be loaded into the skip and hoisted through the skipway shaft defined by the casing to the surface. The casing in effect amounts to a shaft so that there is no interference in hoisting the cuttings material during the cutting and/ or conveying action of the apparatus which operates and is also positioned generally outwardly relative to the casing and which is supported by suitable means during the cutting and conveying operation thereof.

Other objects and important features of the invention will be apparent from a study of the specification following taken with the drawing, which together show, describe and illustrate :a number of preferred embodiments of the invention and what are now considered to be the best modes of practicing the principles thereof. Other embodiments may be suggested to those having the benefit of the teachings herein, and such other embodiments are intended to be reserved as they fall within the scope and breath of of the subjoined claims.

In the drawing:

FIGURE 1 is a vertical sectional view of an embodiment of an improved apparatus for performing a novel method for excavating a pilot hole for use in sinking a mine shaft, or the like;

FIGURE 2 is an enlarged detailed sectional plan view taken along the line 22 of FIG. 1 looking in the direction of the arrows;

FIGURE 3 is a vertical sectional view, similar to FIG. 1, illustrating a modification of the improved apparatus which employs a novel method for excavating the pilot hole in accordance with the teaching of this invention;

FIGURE 4 is an enlarged detailed sectional plan view showing a cutter device and valve means of the modification illustrated in FIGURE 3, taken along the line 4-4 looking in the direction of the arrows;

FIGURE 5 is an enlarged partial view illustrating the details of the cutter device and the valve means of FIG.

FIGURE 6 is a plan view of an embodiment of an improved apparatus for performing a novel method for expanding a pilot hole in an operation such as sinking a mine shaft, or the like;

FIGURE 7 is an elevational view of the invention as illustrated in FIG. 6;

FIGURE 8 is an enlarged partial elevational, view taken along the line 8-8 of FIG. 7 looking in the direction of the arrows;

FIGURE 9 is an elevational view, similar to FIG. 7, of a modification of the improved apparatus employing a novel method for expanding a pilot hole;

FIGURE 10 is an elevational view, similar to FIGS. 7 and 9, of a still further modification of the improved apparatus which employs a novel method for expanding a pilot hole; 7 I

FIGURE ll is an elevational view of an embodiment of a head frame structure as used with the improved apparatus for performing the novel methods of excavating and expanding a pilot hole in accordance with the teaching of this invention;

FIGURE 12 is an elevational view, similar to FIG. 11, of a modification of such head frame structure, and

FIGURE 13 is a schematic illustration of the arrangement of the respective improved apparatus for perfornn ing the novel methods in excavating and expanding a pilot hole used in an operation such as sinking a mine shaft, or the like.

Attention is now directed to the drawing wherein there are illustrated several modifications of the apparatus for performing the improved method of mining in accordance with this invention and which further illustrates the improved method and the preferred modifications of the apparatus employed in a shaft sinking operation.

FIGS. 1 to illustrate the preferred modifications of the improved apparatus for performing the novel method of excavating a preliminary pilot hole 19 which may be extended to the full distance of a proposed shaft 12, as illustrated in FIGS. 6 to 10, before the actual shaft sinking operation starts or which may be advanced in increments of such length so that in either of the modifications the pilot hole will be maintained in advance of a working face 14 of the shaft 12. a sutficient distance to provide a loading zone such as a skip pocket 16 in advance of the working face 14 of the shaft 12, in a manner to be explained in more detail hereinafter. An open ended casing 18 which defines a skipway shaft 29 i positioned within the pilot hole 1% and in accordance with the modification of this invention as illustrated in FIGS. 1 and 2 the casing 18 is in the form of a cutter casing 22 and the pilot hole 10 is excavated, dug, sunk or drilled by rotating the cutter casing 22 having a cutter.

head 24 which includes a cutter device 26 which may be in the form of serrated cutter blades 28 disposed in the lower portion of the rotating cutter casing 22 in spaced relationship to each other, note FIG. 2. The lower end portion of the cutterhead 24 is provided with a plurality of generally radially disposed elongatedcirc'umferentially spaced slots 39 which enable cuttings material that is excavated by the cutter-head 24 to pass generally axially through the lower open end portion of the cutter casing 22. Suitable cutter casing rotating drive and feed means, not illustrated, is provided on ground surface S for rotating the cutter casing 22.. The casing 18 extends generally vertically and terminates upwardly beyond the ground surface S a sufiicient distance to define an unloading zone and enable a suitable skip dump 32,,note FIGS. 11 and 12, to be provided so that the material which is excavated may be readily removed to and disposed of on the ground surface S.

Within the rotating cutter casing 22 there is provided a suction pump or bailer type skip 34 which includes a skip housing orrcylinder 36, piston rod .38 and bailing piston 40 having suitable packing means 42. Attached to the upper end portion of the piston rod 38 is a weight 44 and a skip hoist cable 46. which is attached to any conventional type of hoisting system, not illustrated, which is positioned on the ground surface S for raising and lowering the skip 34 between the skip pocket 16 at the loading zone and the skip dump 32. at the unloading zone,as desired.

The lower end portion of the skip housing 36 is provided with a plurality of spaced openings 48 which overlie in registration with the slots 39 in the cutterhead 24 and one way check type flap valve means 50 may be pivotd ally mounted or hinged to the lower end portion of the skip housing 36 for closing the openings '48 and to enable cuttings material which is excavated by the cutterhead 24 to move into the skip '54 on the upward stroke of the bailing piston 4%.

It is to be noted that the rotating cutter casing 22 is of smaller diameter than the diameter of the pilot hole 10 which is cut by the cutterhead 24 so that there is provided an annular generally cylindrical space 52 between the pilot hole 10 and the rotating cutter casing 22. A conduit :74 which is connected to a water supply such as a reservoir or the like, not illustrated, is in communication with the space 52 through a water supply collar 56 so that water may be flushed and flow down between the cutter casing 22 and the pilot hole 10 into the space 52 to facilitate the removal of the cuttings material which has been excavated by the cutter head 24 so that on the upward roke of the bailing piston 49 the flushing water and cuttings material are flushed into the skip 34 through the open slots 30, openings 48 and the valve means 50 and upon filling of the skip 34 with the flushing water and cuttings material the valve means 50 normally closes to retain the material within the skip '34 and the skip 34 may then be raised to the skip dump 32 by means of the skip hoist cable 46 of the hoisting system and then dumped.

In operation, the cutter casing 22 of the apparatus of the modification illustrated in FIGS. 1 and 2 is rotated by the drive and feed means, not illustrated, to operate the cutter blades 28 of the .cutterhead 24 and the flushing water flowing down around the outer surface of the cutter casing 22 in the space 52 will wash and urge the cuttings material up through the open slots 36, openings 48 past the valve means 50 into the skip 34. When the skip 34 is lowered to the loading position in the lower end of the cutter casing 22 the hinged valve means 50 encounters the cuttings material that has accumulated at the bottom of the cutter casing 22 and the skip housing 36 may or may not sink and slide down around such cuttings material. In any event, when the skip housing '36 comes to rest, the weighted piston rod 38 and bailing piston 40 continue to move downwardly and descend until contact is made with the bottom of the skip housing 36, the valve means 50 or the accumulated cuttings material, as the situation may be. The hoist cable 46 is then pulled upwardly to raise the piston rod 38 and bailing piston 40 and cause an upward flow of the flushing water and cuttings material through the slots 30, openings 48 and valve means 50 into the skip housing 36. As the cuttings material moves into the skip housing 36 the skip 34 generally sinks and thus facilitates the loading operation. When the piston rod 33 and bailing piston 49 reach the upper limit of travel, the skip 34 is raised by the hoist cable 46 of the hoisting system and the cuttings material is trapped within the skip housing 36 above the hinged or pivoted valve means 50. The skip 34 is raised while the cutter casing 22 continues to rotate and the skip 34 is lowered to the bottom and the operation cycle is repeated.

Attention is now directed to FIGS. 3 to 5 wherein there is illustrated a modification of the improved apparatus for performing the novel method of digging, sinking, drilling or excavating the pilot hole 10. In this modification the casing 18 which defines the skipway shaft 20 is a nonrotating casing 58 that is clamped through suitable collar clamping means, not illustrated, at the ground surface S with the casing 58 being of smaller diameter than the pilot hole dtl to define the annular space 52 between the pilot hole 10 and the casing 58 with the conduit means 54 being in communication with the space 52 through the collar 56. A rotating skip 60 is positioned within the casing 58 and includes a skip housing 62 having a cutterhead 64 in the form of an enlarged three bladed auger type bit 66 without spiral flights having a plurality of spaced generally radially disposed openings 68 in the lower end portion thereof. Circumferentially spaced intermediate the blades of the bit 66 there are provided hinged gage cutters 70 which extend generally radially outwardly from the periphery of the skip housing 62. If desired, one way flap valve means 72 may be provided for the lower open end of the cutterhead 64.

In this modification of the apparatus, since the cutterhead 64- is located on the lower end portion of the rotating skip 66 and since the skip 69 is positioned within the casing 58 and further, since it is desirable that the pilot hole It be larger than the casing 58 to define the space 52 therebetween, the gage cutters 70 are each hingeably mounted to the skip housing 62 by suitable means such as pins 7 4 so that the gage cutters 7 0 will normally swing inwardly relative to the casing 58 so that the rotating skip 60 may be raised and lowered between the loading and unloading zones through the skipway shaft defined by the casing 58.

The gage cutters 7i? are hingeably carried by the skip housing 62 so that the cutters 7% will hang generally downwardly a sufiicient amount to clear the casing 58 during movement of the skip fill therein and when the skip 60 descends the cutters 70 will be urged outwardly to the cutting position by reason of the weight of the skip. The skip 60 is rotated within the casing 58 through a drive bar 76 which extends beyond the ground surface S and terminates in a suitable connection to a rotating drive means, not illustrated.

On rotation of the skip 60 through the drive bar 76 the cutterhead 64 removes material from the bottom of the pilot hole 10 and the cuttings material and flushing Water are permitted to enter and fill the rotating skip 60 through the openings 68 of the cutterhead 64 and when the skip 60 is filled it is hoisted to the skip dump 32 on the ground surface S by means of suitable hoisting apparat-us, not illustrated.

In each of the modifications of the improved apparatus for performing the novel method of excavating the pilot hole 10, described above and illustrated in FIGS. 1 to 5, the flushing of the water through the annular space 52 and the slots and openings 43 and 68 of the

skips

34 and 60, respectively, provides a hydraulic head or a difference of pressure between the outside of the

casings

22 and 58 and the inside of the

respective skip

34 or 60 which is effective in moving and conveying the cuttings material into the respective skip for haulage to the skip dump 32.

If desired, a centrifugal pump or reciprocating sand pump, neither being illustrated, may be employed at the bottom of the casing to aid in the removal of the flushing water and cuttings from the bottom of the pilot hole 16 to the ground surface S.

Further, some survey or control should be made during the excavating of the pilot hole It but it is not necessary that the pilot hole be maintained on center relative to the proposed shaft 12 and the pilot hole It) may be oif center, to some degree, and still serve as a shaft guide for the proposed shaft 12 by employing a casing 18 for the skipway shaft that is substantially smaller in crosssectional area than the pilot hole 10 and an eccentric guide for adjusting the skipway shaft within the pilot hole Ill.

In practicing the improved method of shaft sinking in accordance with this invention, after the pilot hole It) has been excavated to a desired distance, that is, either to the entire depth of the proposed shaft 12 or at least to a distance so that the pilot hole 10 will define the loading zone or skip pocket 16 in advance of the shaft working face 14, the ground material which surrounds the casing 18 and which is disposed immediately laterally adjacent to or radially outwardly from the skipway shaft 20 intermediate the end portions thereof is removed by suitable excavating, cutting, and/or conveying means 80 to be described and disclosed in more detail hereinafter, so that the pilot hole 10 is expanded in a generally lateral direction, to a desired cross-sectional area with the result being that the proposed shaft 12 is continuously advanced by first, excavating the pilot hole 1% in a given direction indicated by the arrows A, note FIGS. 7, 9 and 10, to a desired distance and then continuously advancing'the shaft working face 14 in the same general direction, as indicated by the arrows B.

"in practice, it has been found most desirable to have the pilot hole 10 of approximately 6 to 8 feet in diameter and it is possible to easily expand such pilot hole to a diameter of at least 60 feet, or larger if desired, to define the confines of the shaft 12.

For the sake of brevity, in describing and disclosing the various modifications in the method and apparatus for expanding the pilot hole 10, as illustrated in the FIGS. 6 to 10, the casing 18 which defines the skipway shaft 26 and a skip 82 will be indicated by similar and like reference characters, respectively, throughout the several views. It is to be understood that in the modifications of the improved method and apparatus as disclosed, described and illustrated, that the skip 82 may be of any suitable and desired structure and while the skip is illustrated as a common bottom dump type skip, FIGS. 6 to 12, bail type skips 34, FIGS. 1 and 2 and a rotary skip 60, FIGS. 3 to 5, the skip may also take other conventional forms.

In each modification the casing 18 will not only act as a skipway shaft 20 through which the skip 82 may be hoisted but will also provide protection for men who may be working in the shaft 12. It is to be noted that in each of the modifications of the improved method and apparatus for expanding the pilot hole 10 as illustrated in FIGS. 6 to 10 that the casing 18 is provided with a plurality of laterally extending circumferentially spaced openings 84 through which the generally radially or laterally outwardly disposed ground material is passed from outside the respective casing 18 to within the casing and into the respective skip 82 for hoisting to the unloading zone at the skip dump 32 on the ground surface S. It is also to be noted that, as illustrated, the casing 18 includes a series of easing sections and that in the various modifications of the improved method and apparatus the casing 18 is illustrated as including a lower section 86 and an upper section 83. If the pilot hole 10 is extended substantially simultaneously with the advance of the shaft working face 14, the lower section 86 of the casing 18 is provided with the plurality of openings 84 through which the cuttings material is conveyed to the skip 82 in the loading zone at the skip pocket 16 and in this instance, the openings 84 are disposed in longitudinal registration with the working face 14 in a position to receive the cuttings material since the openings 84 are in the lower section 86 of the casing 18 which is advanced with the advancement of the shaft working face 14. If the pilot hole 10 is excavated to substantially the entire depth of the proposed shaft 12 prior to the expansion of the pilot hole 10 then it is. possible to pull the pilot hole excavating casing and add the lower section 86, having the openings 84 therein, and then replace the casing 18 and advance same with the advance of the shaft working face 14 during the expansion of the pilot hole ltl. it is also possible, if necessary, to provide the pilot hole excavating casing with a plurality of the openings 84 with the openings being circumferentially and longitudinally spaced throughout substantially the entire longitudinal extent of the casing so that on completion of the pilot hole Ill it would not then be necessary to pull the entire casing 18 and the excavation operation in expanding the pilot hole 10 would be elfective since there would be openings 84 at any depth which would be in registration with the advance of the shaft working face 14.

In the modification of the improved apparatus for performing the novel method of sinking the shaft 12, as illustrated in FIGS. 6 to 8, the excavator-conveyor means 89 is generally horizontally disposed and extends generally radially or laterally outwardly relative to the casing 13. The excavator-conveyor means 80, as illustrated, is mounted to the casing 18 by an apron guide 90 so that the excavator-conveyor means 351 may move circumferentially or peripherally around the casing 18 as indicated by the arrows in FIG. 89, as illustrated, includes a screw conveyor 92 and a cutter chain 94 is provided. in advance of the screw conveyor 92 for cutting, excavating or removing the ground material from the working face 14 of the shaft 12.' In this modification the conveyor apron guide 99 enables the cutter chain 94- and the screw conveyor 92 to have helical movement relative to the longitudinal axis of the casing 18, note the shaft bottom and working face 14 as illustrated in FiG. 7.'

Inthis modification, it is possible for the casing 18 to be either rotating as the cutter casing 22 above described and illustrated in FIGS. 1 and 2 or non-rotating as the casing 58 above described in FIGS. 3 to 5. In each instance either rotating or non-rotating casings which excavate the pilot holelt), the excavator-conveyor means 39 is rotated in the helical path relative to the longitudinal axis of the casing 18 to effect the desired excavation or cut. In the modification as illustrated in FIGS. 6 to 8 of the drawing, the casing 18 does not rotate and would correspond to the apparatus and method for excavating the pilot hole 10 as described and disclosed above and illustrated in FIGS. 3 to 5.

Intermediate the cutter chain 94 and the screw conveyor 92 there is provideda conveyor apron $6 which enables the cuttings material to be easily moved from the shaft working face 14 into proximity with the screw conveyor 96 so that the cuttings material may be moved toward the casing 18 through the openings 84 and into the skip 82. The excavator-conveyor means St? is driven in the helical path by a motor and suitable gearing means 98 which includes a spiked apron drive wheel 99 that is in engagement with the shaft bottom for moving the excavator-conveyor means 80 into operative position relative to the generally vertically disposed shaft working face 14. Also, the motor 98 is utilized to drive the screw conveyor 92 through suitable gearing (FIG. 6) and to drive the cutter chain 94 through any suitable driving connection (not shown). The helical path through which the excavator-conveyor means 80 progresses in expanding the pilot hole 1%? is a path that is circumferentially around the casing 13 and simultaneously longitudinally downward relative thereto. The improved apparatus of this modification provides a generally vertically disposed working face 14 from which the ground material may be readily removed and while the screw conveyor 92 and the cutter chain 94 have been illustrated as the excavator-conveyor means 84) in this modification, his to be understood that other conventional types of excavators such as pick and shovel, pneumatic hammers, power spades, mechanical boring apparatus, rotating disk cutter bars, etc. and other conventional types of conveying means or systems such as belt conveyors, hydraulic systems, etc. may be used to expand the pilot hole 16' to the desired size and the screw conveyor 92 and cutter chain 94- have been disclosed for the purpose of illustration only. By employing the substantially horizontally disposed generally radially extending excavator-conveyor means 80 which moves in the helical path around the casing 18 the working face 14 and the spiral shaft bottom are advanced by excavating the generally vertical working face 14 slightly below the previous out which is considerably faster and cheaper than removingmaterial from a substantially horizontally disposed shaft bottom.

Attention is now directed to FIG. 9 wherein there is shown a modification of the improved apparatus for performing the novel method of expanding the pilot hole 10 to the desired size in sinking the shaft 12, or the like, which is preferably used in combination with the modification of the method and apparatus illustrated in FIGS. 3 to 5, described and disclosed above, wherein the cas- 6. The excavator-conveyor means ing 18 is non-rotating. .In this modification, a suitable head frame 1%, FIG. 11, is provided for supporting the casing 18 and the excavating means which is, in this modification, in the form of a cutterhead 102 including cutter bars 194 having rotating cutters 106. The cutter bars 1&4 are inclined and converge toward the pilot hole 1% in the direction of advance of the shaft working face 14 so that the shaftworking face is in the form of an inverted cone. The cutterhead 1tl2 rotates about the lower section 86 of the casing 18 and is supported therefrom by suitable cutterhead guide bearing means 108. A thrust collar 11% is provided on the lower section 86 of the casing 18 for supporting a non-rotating cutterhead support structure 112. A cutterhead drive motor 114 is supported on the support structure 112 and is operatively connected through suitable thrust rollers and gears 116 for rotating the cutterhead 102. A cutterhead hoist 118 is supported on the support structure 112 for operatively maneuvering the cutterhead 102 relative to the shaft working face 14 with the hoist 118 being connected to the cutterhead 102 through suitable sheave and cable means 126 which is secured to a ground supported structure 122.

The head frame structure 100, as illustrated in FIG. 11, is preferably used in combination with the modification of the improved method and apparatus as shown in FIG. 9 wherein the casing 18 is non-rotating, and includes a tripod type derrick frame structure 124 which has a skip hoist sheave 126 positioned at the apex thereof about which the hoist cable 46 passes with the hoist cable being connected between the skip 82 and a skip hoist 128 supported on a hoist operating platform 130. In this modification of the head frame structure 100, the upper sec tion 88 of the casing 18 is supported through an upper support collar 132 which is supported upon the hoist operating platform 130 with the support collar 132 arranged to permit sliding adjustment for guiding the lower section 86 of the casing 13 and the cutterhead 102. The lower section 86 is disposed in telescopic relationship with the lower end of the upper section 88 and suitable guide collar means 134 is provided for the telescoping upper and

lower sections

88 and 86. A clamp collar 136 joins the

telescoping casing sections

86 and 88 and a suitable counterweight 138 is provided for the lower section 86. It is to be understood that additional lower skipway sections 86', shown by dotted lines, may be added to the casing 18, in any well known manner, as required during the advancement of the pilot hole '10. The skip 82 is illustrated in solid lines in FIG. 9 as being in the loading zone at the skip loading position in the skip pocket 16 and in dotted lines in FIG. 11 as being in the unloading zone at the skip unloading position in the skip dump 32 wherein the cuttings material which has been removed during the advancement of the shaft 12 may be dumped from the skip 82 which is positioned in the upper casing section 88 with the material passing into a chute 140 through a skipway chute gate 142 having a weighted lever 144 thereon. Suitable telescoping cutterhead torque arms 146 may be clamped and positioned between the cutterhead support structure 112 and the wall of the shaft 12 to provide suitable support as excavating of the shaft advances.

It is to be noted that in the modification of the improved method and apparatus as illustrated in FIGS. 9 and 10 that the shaft working face 14 of the shaft bottom is inclined to the vertical and is substantially conical in configuration with the apex thereof extending downwardly in the direction of advancement of the excavation of the shaft 12 so that the shaft working face 14 converges toward the pilot hole 10 and the casing 18 in the direction of advancement to facilitate in the movement of the cuttings material which is cut by the cutterhead 102 through the openings 84 in the casing 18 for easy loading into the waiting skip 32 which is positioned in the skip pocket 16. r

Attention is now directed to the modification of the improved apparatus for performing the novel method of exca vating, sinking or driving the shaft as illustrated in FIG. wherein the primary difference between this modification and the modification as illustrated in FIG. 9, as disclosed and described above, is that the casing 18 rotates and the instant modification is preferably used in combination with that modification of the method and apparatus for excavating the pilot hole 10 as illustrated in FIGS. 1 and 2 described and disclosed above. In order to enable the casing 18 to rotate, there is provided a flanged portion 148 on the upper end of the lower casing section 86, see FIG. 12, and a cutterhead drive gear 150 is bolted to the flange 148 of the lower section 86. Suitable thrust rollers 152 support the lower section 86 of the casing 18 and the cutterhead 102 and the thrust rollers 152 are in turn supported through a support structure 154 which includes a cutterhead drive frame 156 that is longitudinally moveable in the direction of the arrow relative to the casing 18 by means of a slotted guide frame 158. The cutterhead drive frame 156 has an open portion 160 that permits the additional sections 86 to be added to the casing, as needed. The slotted guide frame 158 takes the cutting torque reaction Which is created through the rotation of the casing 18 and cutterhead 102. During the sinking of the shaft 12 by expanding the pilot hole 10 the cutter drive frame 156 moves between the upper position, as illustrated by the solid lines of FIG. 12, to a lower position adjacent the ground surface S and when the cutter drive frame 156 reaches the lower position, the lower casing section flange 148 is released from the lower section of the casing 18 and the cutter drive frame 156 is raised to the upper position and the additional section 86' of the casing is added as required through the advancement of the shaft working face 14. As shown in FIG. 10 the cutterhead 102 is supported for rotation with the lower section 86 of the casing 18 by means of a cutterhead supporting structure 162 having a collar 164 which is clamped to the lower section 86 for rotation therewith. As illustrated, a non-rotating work platform 166 is secured to the wall of the shaft 12 through suitable anchoring bolt means 168 and supporting rollers 170 support the work platform 166 on the cutterhead supporting structure 162. A cutterhead and casing drive motor 172 is carried by the cutter drive frame 156 and the drive motor is operatively connected to the drive gear 150 to rotate the casing 18 and cutterhead 102. The advancement of the cutterhead 1112 and the positioning of the lower section 86 of the casing 18 and cutterhead 102 are controlled through a cable system 174 which is secured to the cutter drive frame 156 and is operative in response to a hoist 176.

In each of the modifications of the apparatus and method of shaft sinking as described above and illustrated in FIGS. 6 to 10 it is to be understood that if flushing water is used in the excavating of the pilot hole 10 simultaneously with the expansion of the pilot hole to the desired shaft size, the level of such flushing water is maintained below the shaft working face 14 and that the flushing water is fed into the space 52 by suitable conduit means at a level below the openings 84 in the casing 18. Since the apparatus for feeding flushing water to the space 52 when the pilot hole 10 is excavated simultaneously with excavation of the shaft 12, forms no part of the instant invention, it is not disclosed herein. It is contemplated herein, therefore, that the excavation operation of the ground material which surrounds the casing 18 be performed with the pilot hole 10 being dry.

From the above description and disclosure, it is to be understood that in practicing the method of this invention that the apparatus may be used in various combinations which are generally related to the type of ground or material through which the shaft is being sunk and also to whether the method employs the sinking of the pilot hole 10 to the entire distance of the proposed shaft or whether the pilot hole 10 will only be in advance of the shaft working face 14 a sufficient distance to provide the skip pocket 16 and that certain features of the improved apparatus for performing the method of this invention may be interchanged with the corresponding apparatus illustrated in the other modifications.

While the invention has been described in terms of a number of arrangements and embodiments, the scope of the invention shall not be deemed to be limited .by the embodiments and arrangements as herein shown, such other embodiments and arrrangements being intended to be reserved especially as they fall Within the scope of the claims here appended.

I claim as my invention: 1. Apparatus for enlarging the cross-sectional area of an existing pilot hole,

said apparatus comprising, in combination, an elongate open ended casing having a length greater than the depth of such pilot hole,

means supporting the casing with one end portion extending into such pilot hole with the other end portion thereof projecting above ground surface to define a continuous passageway from such pilot hole to ground surface,

said casing having a plurality of generally lateral openings disposed intermediate the end portions thereof at a location therealong which is spaced from the one end portion thereof a distance which is sufiicient to define a loading zone therein,

excavating means carried by the casing and disposed thereon adjacent the lateral openings therein and projecting laterally outwardly therefrom for removing at least that portion of ground material which surrounds the casing intermediate the end portions thereof to expand the area of such pilot hole,

said excavating means being effective to remove such portion of ground material and enable same to pass through the lateral openings in the casing to the loading zone therein, and

means for removing the excavated portion of such ground material from the loading zone to an unloading zone at ground surface,

said last mentioned means being entirely disposed within the confines of the casing and movable through the passageway defined thereby throughout substantially the full longitudinal length thereof between the loading and the unloading zones.

2. The apparatus as set forth in claim 1, together with means for rotating the excavating means relative to the casing.

3. The apparatus as set forth in claim 1 wherein the excavating means is disposed relative to the casing to create a working face which has a surface that is inclined relative to the casing.

4. The apparatus as set forth in claim 1 wherein said casing comprises a plurality of substantially cylindrical sections with adjacent ones of said sections being disposed in end to end relationship relative to each other.

5. The apparatus as set forth in claim 4 wherein that section of the casing which is at the other end portion thereof is supported to telescopically receive that section of the casing which is immediately adjacent thereto, and

that section of the casing which is at the one end portion thereof is provided with the lateral openings.

References Cited by the Examiner UNITED STATES PATENTS 1,033,990 7/12 Connolly 175--l61 1,516,830 11/24 Schafer 262-5 1,834,751 12/31 Upson 61-40 2,000,195 5/ 35 Siebel 61-57 X (Gther references on following page) 1 1 UNITED STATES PATENTS Satre 61- -53.64 Berlin 61--40 Smith ,6153;64

Catland 175344 Love 175344 Wick 614O Sewell 175--309 Thornley 6140 Gregory 175-309 Long 175--57 Van Dusen 21417 FOREIGN PATENTS Germany. France. France.

Great Britain. France.

OTHER REFERENCES German printed application (Meininghaus),- 16,183,

Claims

1. APPARATUS FOR ENLARGING THE CROSS-SECTIONAL AREA OF AN EXISTING PILOT HOLE, SAID APPARATUS COMPRISING, IN COMBINATION, AN ELONGATE OPEN ENDED CASING HAVING A LENGTH GREATERR THAN THE DEPTH OF SUCH PILOT HOLE, MEANS SUPPORTING THE CASING WITH ONE END PORTION EXTENDING INTO SUCH PILOT HOLE WITH THE OTHER END PORTION THEREOF PROJECTING ABOVE GROUND SURFACE TO DEFINE A CONTINUOUS PASSAGEWAY FROM SUCH PILOT HOLE TO GROUND SURFACE, SAID CASING HAVING A PLURALITY OF GENERALLY LATERAL OPENINGS DISPOSED INTERMEDIATE THE END PORTIONS THEREOF AT A LOCATION THEREALONG WHICH IS SPACED FROM THE ONE END PORTION THEREOF A DISTANCE WHICH IS SUFFICIENT TO DEFINE A LOADING ZONE THEREIN, EXCAVATING MEANS CARRIED BY THE CASING AND DISPOSED THEREON ADJACENT THE LATERAL OPENINGS THEREIN AND PROJECTING LATERALLY OUTWARDLY THEREFROM FOR REMOVING AT LEAST THAT PORTION OF GROUND MATERIAL WHICH SURROUNDS THE CASING INTERMEDIATE THE END PORTIONS THEREOF TO EXPAND THE AREA OF SUCH PILOT HOLE, SAID EXCAVATING MEANS BEING EFFECTIVE TO REMOVE SUCH PORTION OF GROUND MATERIAL AND ENABLE SAME TO PASS THROUGH THE LATERAL OPENINGS IN THE CASING TO THE LOADING ZONE THEREIN, AND MEANS FOR MOVING THE EXCAVATED PORTION OF SUCH GROUND MATERIAL FROM THE LOADING ZONE TO AN INLOADING ZONE AT GROUND SURFACE, SAID LAST MENTIONED MEANS BEING ENTIRELY DISPOED WITHIN THE CONFINES OF THE CASING AND MOVABLE THROUGH THE PASSAGEWAY DEFINED THEREBY THROUGHOUT SUBSTANTIALLY THE FULL LONGITUDINAL LENGTH THEREOF BETWEEN THE LOADING AND THE UNLOADING ZONES.