US3856357A

US3856357A - Combination rotor-box cutter mining machine and method of mining

Info

Publication number: US3856357A
Application number: US00390409A
Authority: US
Inventors: G Wharton
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-08-22
Filing date: 1973-08-22
Publication date: 1974-12-24
Anticipated expiration: 1991-12-24

Abstract

A mining machine for the cutting and removal of coal from a coal seam comprising a plurality of rotary kerf cutting means, wherein the latter are utilized together with a surrounding ''''box'''' kerf cutter adapted to cut a rectangularly shaped kerf surrounding the bores and circular cuts of the rotors, thus enabling the ''''corners'''' and intermediate areas of the kerf to be effectively removed. The rectangular cutting mechanism is caused to vibrate or oscillate responsive to rotation of the drive shafts of the rotors via an eccentric drive means incorporated in the said shafts. The rectangular cutter box is rendered adjustable in height by adjusting means in interconnection with cams riding upon an eccentric portion of the drive shafts, thus enabling the ''''box'''' to accommodate different heights of coal seams. The cutter box is also devised to follow irregularities in the seam, and this by forwardly extending and hinged cutting media on the forward cutting end of the box. Also, each rotary cutter is equipped with means to apply suction or pressure at the forward cutting end thereof, to thus remove resultant dust as well as liberated noxious fumes, such as methane gas.

Description

United States Patent [191 Wharton I Dec. 24, 1974 COMBINATION ROTOR-BOX CUTTER MINING MACHINE AND METHOD OF MINING I Inventor: George C. Wharton, PO. Box 450,

Wise, Va. 24293 Filed: Aug. 22, 1973 Appl. No.: 390,409

[56] References Cited UNITED STATES PATENTS Legg Plant Risse 299/80 X Long 299/86 Wharton 299/12 Primary Examiner-ErnestR. Purser Assistant Examiner-William F. Pate, 111

US. Cl 299/12, 175/91, 299/12,

571 ABSTRACT A mining machine for the cutting and removal of coal from a coal seam comprising a plurality of rotary kerf cutting means, wherein the latter are utilized together with a surrounding box kerf cutter adapted to cut a rectangularly shaped kerf surrounding the bores and circular cuts of the rotors, thus enabling the comers and intermediate areas of the kerf to be effectively removed. The rectangular cutting mechanism is caused to vibrate or oscillate responsive to rotation of the drive shafts of the rotors via an eccentric drive means incorporated in the said shafts. The rectangular cutter box is rendered adjustable in height by adjusting means' in interconnection with cams riding upon an eccentric portion of the drive shafts, thus enabling the box to accommodate different heights of coal seams. The cutter box is also. devised to follow irregularities in the seam, and this by forwardly extending and hinged cutting media on the forward cutting end of the box. Also, each rotary cutter is equipped with means to apply suction or pressure at the forward cutting end thereof, to thus remove resultant dust as well as liberated noxious fumes, such as methane gas.

12 Claims, 7 Drawing Figures I i n 96 I "mi I T4 3 11. 1 H n l=;:-!*E"EIEEIS!EI I I 95 5 "I,

85 I 15 96 Z I l' 78 I 5a I i n r PATENTED DEC 2 4 I974 saw 2 o g PATENTEB BEB24 I974 sum 3 or q BACKGROUND OF INVENTION AND PRIOR ART The instant invention is directed to a coal mining machine utilizing two basic operations insofar as the cutting operation be concerned. Firstly, at least two types of rotor type of boring devices are employed, each one of same being provided with a forward extending bursting tool for fracture of the coal at the point of penetration thereof. Secondly, and in conjunction with the foregoing, I employ a rectangular and socalled cutter box" of unique design. The latter is of rectangular configuration and thus adapted to penetrate the face in rectangular fashion around that portion cut by the aforementioned rotor device. The resultwis to increase the recovery of mined, shattered coal by recovery of same at the four rounded corners left by the augers or rotors, as well as loose material above and below auger penetration which clings to the roof and floor of the minenConsequently, a practically 100 percent recoveryvis obtainable unless intervening pillars are deliberately left underground, which is often the case for mine roof support.

There is another basic facet of this invention which, in a sense, is related to the invention of my US; Pat. No. 3,726,562. Although this latter patent describes a somewhat different form of kerf cutting media, it emphasizes a theme of suction removal at the working face of accumulations of dust as well as noxious methane gas, always a hazard in mining operations. In the instant invention, this same concept is carried out by the application of either pressure or suction at the working face. Such is applied via airflow through a pipeline representing a center bore through the axis of the shafts which support and rotate the auger or rotary cutter means. Since the latter terminate at the faceof the mine, the applied pressure or suction in the construction herein described below is also applied near the working face and for the purposes above mentioned coal dust and methane removal. As an alternate to suction, air pressure may be used. In this regard, it is of course to be understood that in modern mining practice it is customary to use relatively high pressure air pumping equipment for mining ventilation, this resulting in airflow toward the mine opening. Hence application of pressure at the face simply adds to that outby air stream already present in the mine shaft and thus fur-' ther assures that such pressure, applied to the face, renders certain the exit of deleterious dust and gas to the mine opening.

Previous adventurers in the art have used the rotor principle, such being accompanied with a center burster device to fracture the face inthe manner more or less contemplated by the instant invention. In this regard, the Jamison, et al., US. Pat. No. 2,868,526 and the Von Stroh US. Pat. No. 2,868,527 are of interest and typical of other prior art illustrative of this type of continuous mining. Jamison, et al., does indicate use in conjunction with the rotor type of mechanism a form of cutter chain tovremove the tusks which remain from the kerf initially impacted by the rotor devices. However, chain cutters are well known to the art; yet that particular set up represents a power mechanism of considerably more complex nature because of the type of drive necessitated. Hence the latter are to be distinguished from the far-simpler, rectangular, adjustable in height mechanism of the instant invention, and as will be apparent from the below particularlized description of my invention.

Rectangular cuts via suitable mechanism, usually the chain type, are furtherillustrated in the patent to Robbins U.S. Pat. No. 2,711,889. Also other devices in the art illustrate certain types of rotors which, in a sense,

have been promoted as enabling a rectangular form of cut (see the Olson US. Pat. No. 2,825,544). However,

none of such prior art utilizes or relates to mechanisms of the type herein described which are not only more simplified in nature, but far more efficacious for the purpose of taking advantage of both the auger and tusk removal systems in combination. Furthermore, none of the prior artas hereinbefore mentioned employs these mechanical arrangements in conjunction with use of pressure or suction at the face and, specifically, in the manner which this facet of the invention is herein disclosed. Certain patents cited in my US. Pat. No. 3,726,562 are more specific to the application of suction at the face. Here again, however, these are not employed inconjunction with a combination type of rotorcutter box arrangement which herein represents the basics of my invention. In this latter regard, the Reeder US. Pat. No. 2,375,689 also illustrates use of suction but in a totally different manner and with regard to an utterly different mechanical arrangement. Certain of the other references cited in my aforesaid patent likewise describedifferent media for application of suction and particularly use of same with totally different types of cutting mechanisms. Hence, the instant combination represents a novel concept over such known prior art.

OBJECTS AND SUMMARY OF INVENTION It is thus the primary object of my invention to promethod and means used in conjunction with the forego-- ing miningmedia to assure that the dust created by the mining and the noxious methane gas often characteristically released by mining operations are removed and this by the application of either pressure or'suction at or near the mine face, such pressure differential being applied via airflow through appropriate bores in the drive shafts of the rotors themselves.

Another objective of the invention is to provide a mechanism of the foregoing type adaptable to the miningof seams of extremely low height yet enabling con each auger or burster means. Such flights function to immediately convey the removed and lumped coal to the rear of the machine where it can be transferred to more conventional conveying equipment for transport to the mouth of the mine. As a matter of fact, and as explained in my aforesaid patent, the conveying operation may be one of a pipeline type relying upon a suction (or pressure) line extending from the last of such flights away from the face of the mine to the opening of the mine shaft, this particularly where the cut matter is of a size adaptable to conveyance in this penumatic fashion, i.e., lump coal of about 2 inches or less in diameter.

A further object of the invention is to provide a mining machine of the type herein described wherein additional intermediate lengths of conveying flights can be attached to the rearward one affixed to the mining head by retraction of the drive mechanism an appropriate distance, insertion of the new flight, andattachment to the rearward flight by specific means to be described, each flight, of course, having a shaft provided with a suitable bore matching the bores of the others so that the function of the supply of air under pressure or withdrawal of air (vacuum) is effectively applied at or near the cutting heads and for the purposes mentioned in the foregoing.

Another object of the invention is to provide a mining machine which, in performance of its ultimate functions, contributes to the ever present aspect of environmental protection by furnishing means to recover minerals, and coal in particular, from under steep mountain slopes and in those areas where'strip mining has been prohibited by governmental regulations. In this sense, the mechanism of the invention permits, for all practical purposes, elimination of stripping in steep terrain where normal run-off of surface water does, more normally than not, deleteriously affect purity of the water as well as animal life downstream from the stripped area.

An additional object of the invention is to provide a mechanism of the type described which represents a fully adequate tool for initial preparation of a mining mouth for opening new mines, yet at the same time offers a mechanical arrangement which is adaptable to underground deep mining where an exceedingly high proportion of coal or other mineral may be removed under poor roof and bad mining conditions, transported back to main haulageways, and this without exposure of men during this recovery of the bulk of the mined tonnage.

Other objectives and advantages of the invention include the following: a machine adaptable to swift, efficient boring to afford underground mine rescue, fire prevention or cutoff of underground fires; a mechanism adaptable to force air through pillars underground as to areas temporarily blocked by roof failure; and finally, a machine which by its very nature represents exceptional efficiency in the elimination of the usual multitude of cutting, shooting, loading, hauling, roof bolting and other manual effort stages requiring accessory equipment, thus to reduce the number of men necessary for such operations to the absolute minimum.

DESCRIPTION OF THE DRAWINGS The structure and mode of operation of the mining machine of this invention may be more clearly understood by reference to the accompanying drawings which illustrate a preferred embodiment thereof, and in which:

FIG. 1 is a side elevation view of the mining machine of this invention;

FIG. 2 is a plan view of the mining machine illustrating the use of at least two boring heads and, with FIG. 1, the manner of penetration into a seam of coal or other mineral material; I

FIG. 3 is a front elevation view, partly in section, illustrating in more detail the construction of the surrounding cutter box, the manner of imparting oscillatory or vibratory movement to said box, and as well, the means utilized to permit vertical extension and retraction of the cutter box thereby adapting the same to seams varying in height or depth;

FIG. 4 is a detailed section view, taken on the line 4-4 of FIG. 3, showing the more particular relationship between the rotating cutterheads and the surrounding cutter box, the manner of varying the height of the cutter box, and with regard to the latter, also indicating the use of movable, hinged cutting teeth mounted on the forward edge of the cutter box enabling the latter to more effectively follow variations in seam contour;

FIG. 5 is a view, diagrammatic in form, indicating the nature of the two cuts made, first the kerf penetration of the rotors and secondly, the lines of cut of the surrounding rectangular cutter box;

FIG. 6'is an enlarged view, partially in section, illustrating the manner of interconnection of two adjacent flights, the latter being provided with an internal bore representing an air passageway with these flights being so attached as to render that passageway airtight therebetween; and

FIG. 7 is a view taken on the line 7-7 of FIG. 6.

MORE PARTICULAR DESCRIPTION OF THE INVENTION With reference now to particularly FIGS. 1 and 2, the forwardly extending rotary cutting devices are generally indicated at l, and the surrounding cutting box structure generally shown at 2. Each of these two primary components of the assembly are supported upon a rotatable shaft 5 which, as to the outby extension thereof, is provided with helical or ribbon conveyor flights 7. Such shafts and flights, the latter of course provided for extended transport of the mined material, are in turn interconnected with a drive mechanism therefor and as more or less diagrammatically shown at 10. This drive mechanism, containing suitable transmission devices of the usual type, and as well, means well known to the art for advancement and retraction of the rotorcutter box arrangement, rests upon an un derlying structure 11 which in turn is supported by two stanchions, a forward one l2and a rearward one 13. Such stanchions, and as also usual in the art and at their lower terminal ends, are mounted for transverse movement upon suitable rails 14 with an interconnecting means 15, including rollers 16, which permit sideways or lateral adjustment of the carriage. Means not shown, but also known to the art, may also be provided for adjustment of the height of the carriage above the mine floor. These variables in adjustment are of course provided for deviation of the machine, laterally or vertically, and in those amounts necessary to follow with reasonable accuracy corresponding deviations of the seam being mined.

As noted above, each drive shaft 5 is provided with an internal and axial bore throughout its length. Such forms an air passageway. This bore, with respect to the first shafts connected to the rotors, is in turn provided with one or more air exit or air inlet openings near the face of the seam as indicated at 21. The latter are preferably located immediately rearwardly of the cutter box assembly.

Adjacent lengths of flights are attached together by means which assure an airtight fitting between lengths, meaning particularly airtightness with regard to the interconnection of adjacent bores in adjacent shafts. That latter means is generally indicated at 22 in FIG. 1 and will be further described below with respect to FIG. 6. Each shaft is interconnected with compressed air or vacuum lines 25, 26 (FIG. 2) the latter being provided with suitable means for feed-in or withdrawal of air with regard to bores 20 while such shafts are being rotated during the cutting operation. Air pressure or vacuum lines preferably extend to the rear of the machine. It is to be noted that the

lines

25, 26 feed into a slip connection or rotary coupling as at 28, 29, the latter being well known to the art. These slip connection devices permit of an airtight connection to the bore 20 despite continuous rotation of the shaft 5.

The forwardly extending rotary cutting and/or trepanning devices will now be more particularly de-- scribed, and with particular reference to FIG. 4. Here it is seen that the burster element 30 is affixed to the forward end of the rotating drive shaft 5. Circumscribing this axially disposed, central cuttingelement 30, is positioned a tubular or cylindrical element 'which is adapted to rotate with the burster and provided with its own forwardly extending cutting elements. This latter device 35 is affixed to and supported by the first one or two flights of the helical screw device 7, as by welding or any other suitable manner, and as depicted in FIG. 4.

The burster 30 is conically shaped at its forward end as indicated by such forward surface 41, the angle of that latter surface being approximately 45 to the axis of the shaft 5. Preferably the back of edge or surface of the burster 30 represented by the numeral is similarly of conical configuration and angled to the axis of shaft -5 and such angle, indicated by the numeral 42, in

thereof consequent upon wear after use. Also, consistent with the object of transferring any cut and/or particulate material rearwardly or to the outby end of the machine, the tubular element 35 is provided with an helical screw formation 52 adapted, upon rotation of each of the cutter assemblies 1, to propel cut, particulate matter to the rear of the machine and for conveyance to the rear via the initial and one or more following extensions of the helical flight 7. By the foregoing description of the forward cutting assembly 1, it should thus be appreciated that its purpose is to penetrate and fracture the coal center and where two of such devices are used in combination, as here shown, to cut two circular kerfs around the center and into the seam S. These are-diagrammatically shown at K in FIG. 5.

As briefly stated in the foregoing, there is also positioned immediately behind the rotating structure 1 or in the relative position shown in FIG. 4, the rectangular cutter box arrangement which is adapted to a rectanguaccommodate, within some limitation, the variation in height of the given seam or vein. To this end, the cutter box is made of two halves, upper and lower, which are arranged for adjustment with regard to each other.

- Taking first the lower half of this cutter box arrangethis embodiment of the invention, is approximately 120 to the axis of the shaft. Naturally, the forward conical shape of the burster is to perform that function which the very name indicates penetration of the seam with such conical surface behind the cutter bit effectuating a bursting effect upon the coal or mineral being mined. It is to be noted in this version of the in- 4 which further facilitates center penetration of the I coal seam.

Referring again to-the tubular cutter element 35, this too is provided with forwardly extending cutter bit holders 48 in which a suitable type of cutter bit 50 is positioned, usually in a manner to permit replacement ment and referring to FIG. 3, it is seen that the bottom thereof is provided with two side elements 58. These are joined together by forward scoop members 59 on each side as well as an aft scoop member 63 of similar configuration, and as indicated in FIG. 4. Such scoops are positionedas represented in FIGS. 3- and 4, i.e., they are'placed inthe lower corners and on each side of the lower half of the cutter box such that with forward motion of the machine the same tend to force cut material toward and into the helical screw conveyor for the obvious purpose of facilitating transfer of the material to the rear of the machine. The after scoops 63, similarly located in the lower cornersof the outby end of the lower half of the cutter box are utilized for the same purpose, i.e., to force material towards the screw conveyor mechanism when the machine is retracted from its cutting position. In both instances such scoops are welded to the bottom wall in the cutter box as at 60 as well as to the side walls-58 of the lower half of the cutter box and as indicated at 62, to thus adequately and integrally secure side wall 58 to the bottom wall 55 of this lower half of the cutter assembly.

Theupper half of the cutter box is of a configuration to match the lower half in sliding relationship and with means to adjust the amount it overlaps the lower half of the cutter box, thus varying the overall height, in a manner which is described below. At any rate, the

upper half cutter box, provided with a top wall 65, is likewise provided with two side walls 66. The dimen amount of this overlap and hence within the discretion of the operator varying the overall height of the entire cutter box assembly.

As mentioned in the foregoing, this entire cutter box assembly 2 is subjected to a slight oscillatory or vibratory motion simultaneously with the rotation of the forward assembly 1, the purpose of such oscillatory motion simply being to cut a rectangular kerf into the face of the mine and again as diagrammatically illustrated in FIG. 5 (K), this oscillation naturally tending to shatter and/or segment into small particles the material which remains after initial cutting achieved by the two rotary or auger mechanisms.

To obtain this vibratory motion, the cutter box is mounted in conjunction with an eccentric or offset portion formed in the main shaft 5. For example and viewing FIG. 4, it is seen that said shaft 5 has a center axis as indicated at dotted line B whereas the center line of the offset portion of the shaft 5 is indicated at dotted line C. The latter represents but a very small offset, comparatively speaking, but fully sufficient tocreate and maintain this simultaneous vibratory motion and for the purposes mentioned.

Accordingly, the cutter box is supported, and with regard to each rotor axis, by the main shaft 5 but here with regard to an eccentric portion 70 and this with respect to such main shaft.

Although two eccentric portions of the shaft are indicated in the drawings with respect to each rotor assembly. the elements comprising the support are the same in each instance and the numeral designations indicate like components with regard thereto. Thus the top of the cutter box in each instance has dependent therefrom a collar or tubular element 77 extending vertically to the shaft 5. Likewise the bottom of the box is similarly equipped with an upstanding collar or tubular element 77. In each instance 77 and 77' are bored to receive on the one hand threaded shaft 74 (the upper shaft) and a lower threaded shaft 75, and as so illustrated in FIG. 3.

When these

shafts

74, 75 are fitted within the appropriate bores in the referred to tubular elements, then each is maintained in the required position of support by take-up of the two

nuts

78 and 80, referring to those take-up devices with reference to the lower and upper threaded elements respectively. Each of the tubular elements is securely affixedto the top and bottom sides of a cutter box casing by welding 79 or other applicable mode within the skill of the art. Each of the

elements

74 and 75, threaded at their outer ends as indicated, is fitted at the opposite ends with a split journal, in the one instance 71 with regard to 74, and in the other 72 with regard to 75, these split journals being secured to- -gether when the entire assembly is in place by the usual bolt means 73.

It is of course obvious that these off-center or eccentric portions of shaft 5 may be turned upon that shaft as an integral portion thereof. However, in the preferred form of assembly and for simplification of fabrication and removal, a stub shaft 84 is used which is seated within an appropriate bore 85 in the main shaft 5. This stub shaft contains that central portion 70 which is eccentric, as explained, with regard to the center axis of the main shaft 5. When located in the position shown in FIG. 4, the stub shaft is maintained in place by pins 86, and as there illustrated.

As should be apparent from the foregoing description, these cooperating elements which are attached to the offcenter or eccentric portion of the drive shaft 5 perform two functions: The first is to support the rectangular cutter box and to support the same in a manner which permits of variation in height thereof. In other words, if the

shafts

74 and 75 in each instance are withdrawn from the respective tubular elements 77 and 77' a predetermined distance from that shown, for example, in FIG. 3, then the bottom and top portions and respectively) of the cutter box are separated. With locking of these shafts 74 and at that distance via

nuts

78 and 80, the vertical height of the cutter box is increased. Corresponding reversal of movement results in a decrease in height. Secondly, this arrangement permits of the oscillatory movement imparted to the cutter box and in all directions consequent upon its mounting on the eccentric portions of shaft 5 or the eccentric portion of the stub shaft 84 as the latter has been previously described. Such manner of mounting to achieve this twofold objective results in the further advantage that support for the rectangular cutter box is simplified, the mode of power for vibratory effect is rendered simpler in construction and operation and the problem of maintenance and repair significantly reduces manpower requirements which are ever present with regard to more complex types of continuous mining machinery.

As stated with regard to both rotors, this assembly described in the foregoing is exactly'the same with regard to'each eccentric mechanism and as may be appreciated from reference'to FIG. 3 where the cutter box is shown as supported by these raised assemblies which, of course, are mounted in exactly the same manner so that the same amount of eccentricity in the same direction is exerted with regard to all sides of the cutter box.

Consistent with the principle that as much cutting be effectuated as possible and also that means be utilized to keep all moving elements clear of binding influences, this cutter box is provided with bits interspersed around its entire periphery and as well upon the rearward end thereof as also shown in FIG. 4. The rear bits are, of course, suitable for assuring adequate clearance and removal of material during retraction of the mining machine.

More importantly, this cutter box assembly is provided at its forward end with a series'of cutter bits positioned within suitable bit holding devices 96 to enable replacement of the bits themselves after periods of normal wear. These forward bits. 95 are disposed in novel fashion in the sense that they are permitted to deviate a small amount and as indicated by the arrow shown opposite such bits in FIG. 4. The purpose of an assembly permitting deviation within perhapa an inch or two is to enable the cutter box during its vibratory movement to adjust somewhat to variations in some height and width and also to obviate or bypass extremely hard materials or consist normally encountered in coal mines such as sulfur balls and iron pyrite formations. a

The movement of the bits 95 is as indicated limited. Such bits are positioned upon a movable flap support means 97 that in turn has a rearward bore to receive a pin 98 about which the support means 97 is permitted some measure of deviation. A stop means 99 limits the movement outwardly (viewing FIG. 4) whereas an angular cut 100 into the forward edge of the cutter box permits movement inwardly only a like amount, in

other words, that amount indicated by the arrows of cutting, but also the function of adequate clearance for withdrawal of the machine, the helical conveyor means 7, and again upon the external edges of the ribbon flights, is similarly provided with a series of cutter bits 120 and again as shown with regard to FIG. 4.

In the foregoing much has been made of the fact that it is desired that upon detachment of a forward helical flight, an additional flight may be added thereto by retraction of the machine drive components of the cutter (i.e., the assembly 10 and mechanism associated therewith) an amount adequate to insert and attach to the forward flight an additional flight. Since, however, it is desired that a primary function of air pressure or vacuum be applied adjacent to the area being mined, each such flight that is added is mounted upon a shaft that similarly is provided with an air inlet-exit bore 20. Themeans for interconnection and to assure against leakage is represented in FIGS. 6 and 7.

Here it is seen that the forward flight terminates in a male element or extension 110, square in cross-section configuration, the latter being adapted to fit into a complementary female bore in the flight to be added. The latter also contains an enlarged circular recess, as shown in FIG. 6, to accept a washer 115 of a type familiar to the art, and fabricated of somewhat compressible material, thus to act as a seal against air pressure leakage. Naturally. such element 115 is provided with an aperture 116 of the same diameter as the bore in each of the drive shafts. Once these elements as thus far described are positioned in the relationship shown in FIG. 6 with the male element bearing tightly against the seal 115, the two facing adjacent ends of the shafts 5 are maintained in sealed relationship in the position shown by a spring means 120, one end of which is bolted by bolt 121 to the end of the shaft having the female bore therein. At its opposite end, this flexible spring element 120 is provided with a locking lug 125 the forward end of the cutter box is located about inches rearward from the tips of the forward auger cutting teeth, and such dimensions as well as others, are

illustrated by theratios of relative sizes shown, for example, in FIG. 4.

With regard to the eccentric mountings described in the foregoing (i.e., the eccentricity used to impart oscillatory motion to the box) the bearings there shown should, of course, be self-lubricating by media well known to the art.

Such construction with this rectangular cutter box slightly behind the rotary cutters, and with the cutter box having imparted to it a slight oscillating motion resultant upon eccentric drive through the auger shafts, results in an operation wherein the four corners around the round drilled holes effectuated by the rotors, will plane off the coal (or other material) clinging to the roof and floor of the mine. It thus will, in effect, bore a square hole, cutting out the material also which is left in between the two round bores in the face and result in, as again stated, a square out here typified diagrammatically by K of FIG. 5.

adapted to seat in a suitable bore 128 in the shaft of the forward flight, so that when positioned as shown such lug maintains these adjacent shafts in secure and fixed alignment and also in a sealed relationship with respect to the common bore 20. The result is that as many flights may be added as appears to be desirable but still with effectively sealed air pressure (high pressure or vacuum) being fed through the shafts of each to the desired area that area adjacent the actual cutting operation.

As a practical application of the mining machine described in the foregoing, it is considered that in the first instance at least two cutting augers be employed, to thus assure adequate support of the rectangular cutter box as well as assure that the same will not materially deviate with regard to both its lateral and vertical planes of operation. A practical size of each auger is about 30 inches with a twin auger unit having about a inch cut and with the cutter box having approximately a 36 inch high by 70 inch wide cut. Preferably Viewing FIG. 2, which illustrates two companion rotary augers for initial cutting, the flights as there depicted are arranged for clockwise movement to thus convey movement to the rear of the machine. However, it is preferred that one flight operate in a clockwise manner and that the adjacent flight and rotor rotate counterclockwise, this being as indicated by the arrows shown in FIG. 3. The purpose of this is, of course, to force cut material toward the area between the rotors where it can more easily be picked up by the adjacent flights and transported to the outby end'of the machine. In such an instance and again viewing FIG. 2, the lower flight is properly depicted with the ribbon conveyor portion thereof upon clockwise rotation forcing or conveying material to the outby end of the mine. However, where the upper flight. as there shown is rotating counterclockwise then of course the flight (although not here shown) would be of reverse configuration or configuration opposite to that shown in the flight rotating clockwise, and again for the purpose of conveyance rearwardly of the cut material.

As may be appreciated from the foregoing, the instant invention is proposed as a mining machine containing'an unusual combination of structural elements which, although following in one way traditional use of boring augers, radically departs from the art in utilizing a surrounding cutter box mechanism 1, which, unlike conventional chain cutters of the prior art, is motivated through the same power source and by the simplest of media oscillatory or vibratory movement is imparted to the box by forces resultant upon eccentricity of those portions of the drive shafts which in turn also provide complete, yet adjustable, support for the cutter box itself. Furthermore, and in line with certain of the materials to the mine mouth and as a booster to ordinary and usual mining ventilation, or by more positive withdrawal of such material by the application of suction near the face of the mine and adjacent to the involved cutting mechanism. In eithercase such dust and fumes are transported to the mine mouth by suitable pipeline conveyance.

It is obvious that other expedients and alternates may be used without departing from the scope of my invention, but such scope thereof is to be determined only by the various limitations directed to the invention which appear in the following appended claims.

I claim:

1. In a coal mining machine the combination comprising a rotor means having a burster element on the forward end thereof, a tubular element with forwardly extending cutting means surrounding and in axial alignment with said burster element. means to rotate said rotor means and said tubular element including a drive shaft means therefor, a rectangular cutter box means having forwardly extending cutters at the forward end thereof, said cutter box means being of a dimension exceeding the crosssectional area of said tubular element, and means in interconnection with said drive shaft to impart oscillatory motion to said cutter box means.

2. The invention as defined in claim 1 wherein said drive shaft means is provided with air delivery means therewithin to exit air to or withdraw air from an area immediately adjacent the rearward end of said cutter box means.

3. In a coal mining machine the combination comprising a rotor means having a burster element on the forward end thereof, a tubular element with forwardly extending cutting means surrounding and in axial alignment with said burster element, means to rotate said rotor means and said tubular element including a drive shaft means therefor, a rectangular cutter box means having forwardly extending cutters at the forward end thereof, said cutter box means being ofa dimension exceeding the cross-sectional area of said tubular element. means in interconnection with said drive shaft to impart oscillatory motion to said cutter box means, and air delivery means within said shaft means to exit air to or withdraw air from an area immediately adjacent the rearward end of said cutter box means.

4. The invention as defined in claim 3 wherein there is provided at least two rotor means in side by side relationship and said cutter box means is of a dimension to exceed overall the size of the kerf cut by said bursters and said tubular element.

5. The invention as defined in claim 4 wherein each of said drive shaft means is provided with helical conveyor means to convey the material cut to the outby end of said mining machine.

6. The invention as defined in claim5 wherein said 12 helical conveyor means is provided with cutter bits on the edges thereof to permit facile retraction of said mining machine.

7. The invention as defined in claim 5 wherein there is provided a plurality of helical conveyor means, each of said drive shaft means having an axial borefor air delivery therethrough, and means to interconnect each of said conveyor means, said interconnecting means including means to render said air delivery of one drive shaft means airtight with respect to an interconnecting, adjacent drive shaft means.

8. The invention as defined in claim 3 wherein said burster element has a forwardly extending, axially positioned cutter bit, and said cutter box means is provided with rearwardly extending cutter bits to thereby facilitate withdrawal of said mining machine from the mine face.

9. The inventionas defined in claim 4 wherein the said two rotor means are driven in opposite directions to thereby force cut material therebetween into the area between said conveyor means to thereby facilitate transport of said material to the rear of said mining machine.

10. The invention as defined in claim 3 wherein said means to impart oscillatory motion comprises-an eccentric drive means on said drive shaft means.

11'. The invention as defined in claim 10 wherein said cutter box means is entirely supported by said drive shaft means.

12. A method of mining into a mineral seam comprising driving a rotating bursting element into the face of said seam to fracture the seamm into particulates at points of contact thereof, simultaneously rotating a tubular cutting element in axial alignment with said bursting element to cut a circular kerf around said burster element to thereby fracture the seam into particulates between said cutting element and said bursting element, immediately following said simultaneous bursting and cutting operation by cutting a rectangular kerf larger in dimension than the cross-sectional area of said circular kerf around the fractured zone of the seam resultant upon said bursting and cutting steps, said rectangular kerf cutting being accomplished via oscillatory motion of a closed, rectangular cutter, said rectangular cutter being oscillated by off-center rotation of the axes of rotation of said cutting and bursting elements, simultaneously conveying the said particulates away from said seam, and applying air pressure or vacuum at a point adjacent said bursting, cutting, and rectangular kerf cutting operations to thereby simultaneously remove fine dust particles and noxious fumes therefrom.

Claims

1. In a coal mining machine the combination comprising a rotor means having a burster element on the forward end thereof, a tubular element with forwardly extending cutting means surrounding and in axial alignment with said burster element, means to rotate said rotor means and said tubular element including a drive shaft means therefor, a rectangular cutter box means having forwardly extending cutters at the forward end thereof, said cutter box means being of a dimension exceeding the crosssectional area of said tubular element, and means in interconnection with said drive shaft to impart oscillatory motion to said cutter box means.

3. In a coal mining machine the combination comprising a rotor means having a burster element on the forward end thereof, a tubular element with forwardly extending cutting means surrounding and in axial alignment with said burster element, means to rotate said rotor means and said tubular element including a drive shaft means therefor, a rectangular cutter box means having forwardly extending cutters at the forward end thereof, said cutter box means being of a dimension exceeding the cross-sectional area of said tubular element, means in interconnection with said drive shaft to impart oscillatory motion to said cutter box means, and air delivery means within said shaft means to exit air to or withdraw air from an area immediately adjacent the rearward end of said cutter box means.

6. The invention as defined in claim 5 wherein said helical conveyor means is provided with cutter bits on the edges thereof to permit facile retraction of said mining machine.

7. The invention as defined in claim 5 wherein there is provided a plurality of helical conveyor means, each of said drive shaft means having an axial bore for air delivery therethrough, and means to interconnect each of said conveyor means, said interconnecting means including means to render said air delivery of one drive shaft means airtight with respect to an interconnecting, adjacent drive shaft means.

9. The invention as defined in claim 4 wherein the said two rotOr means are driven in opposite directions to thereby force cut material therebetween into the area between said conveyor means to thereby facilitate transport of said material to the rear of said mining machine.

10. The invention as defined in claim 3 wherein said means to impart oscillatory motion comprises an eccentric drive means on said drive shaft means.

11. The invention as defined in claim 10 wherein said cutter box means is entirely supported by said drive shaft means.