US3640580A

US3640580A - Dust-eliminating coal-mining apparatus

Info

Publication number: US3640580A
Application number: US844269A
Authority: US
Inventors: Letcher T White
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-07-24
Filing date: 1969-07-24
Publication date: 1972-02-08
Anticipated expiration: 1989-02-08

Abstract

A coal-mining apparatus is fed against a vein of coal under pressure and advanced through the vein to progressively mine the coal. Back of the mining apparatus is arranged a board or partition which extends from the floor to the roof of the mine and combines with the floor and with the veil of coal to form a compartment. Means is provided, associated with the compartment referred to, for minimizing or eliminating light floating dust, this being done either by spraying through the air in the compartment or by exhausting air therefrom. The invention further comprises a method of coal mining wherein the mining operation takes place in a confined space, and, during the mining operation, coal dust is constantly eliminated from said confined space.

Description

United States Patent [151 3,640,580

White [451 Feb. 8, 1912 [54] DUST-ELIMINATING COAL-MINING 3,439,508 4/1969 Payne et a1 ..299/12 X APPARATUS 3,445,139 5/ 1969 Von Hippel.

3,464,756 9/1969 Burgess .Il299/12x [72] Inventor: Letcher T. White, 117 Wayne Street,

Manchester Y- 40962 Primary Examiner-Emest R. Purser 22 Filed: July 2 19 9 Attorney-John X. Phillips [21] Appl. No.: 844,269 [57] ABSTRACT A coal-mining apparatus is fed against a vein of coal under [52] US. CL ..299/31, 299/12, 299/ 18, pressure and advanced through the vein to progressively mine 299/31, 2 9/87 the coal. Back of the mining apparatus is arranged a board or [51] Int. Cl. ..EZlc 35/22 partition which extends from the floor to the roof of the mine Field f Search 1 and combines with the floor and with the veil ofcoal to form a compartment. Means is provided, associated with the com- [56] References Cited partment referred to, for minimizing or eliminating light floating dust, this being done either by spraying through the air in UNITED STATES PATENTS the compartment or by exhausting air therefrom.

1,131,852 3/1915 Morgan ..299/ 12 X The invention f th comprises a method f coal mining 1,982,470 1 1/ 1934 Franks 2 9/ X wherein the mining operation takes place in a confined space, 2,408,967 10/ 1946 Brown 299/18 x and, during the mining operation, coal dust is constantly 2,693,950 1 l/ 1954 Calder v.299/12 X eliminated f Said fi d Space 2,891,778 6/1959 Milik ...299/18 X 3,333,896 8/1967 Diarnantl ..299/19 X 11 Claims, 16 Drawing Figures PAIENTEDFEB' 8 m2 snzsr 1 or 5 ATTORNEY PATENTEBFEB 8 ma 3.640.580

sum 3 or 5 5a F76. Z

I5? 224 INVENTOR L efcher 7 W/w'f'e BY W ATTORNEY PATENYEDFEB e 1912 sums ms 1 NVENT OR L eftfier Z' W/v/fc ATTORNEY DUST-ELIMINATING COAL-MINING APPARATUS CROSS-REFERENCE TO RELATED APPLICATION Reference is made to applicant's copending application Ser. No. 769,574, filed Oct. 22, 1968. In such application, a helix having hardened steel points fixed at spaced points along the edge of the helix is advanced into a vein of coal laterally of the helix, and means is provided for moving the helix vertically to mine coal throughout the height of the vein. Rearwardly of the helix is arranged a board extending from the floor of the mine to a point spaced thereabove to form with the floor of the mine and the vein of coal a trough into which the mined coal falls, and the helix, carrying the cutting points, serves as a conveyor for moving the coal endwise of the trough for suitable collection to be hauled to the mouth of the mine and discharged.

BACKGROUND OF THE INVENTION The invention relates to the mining of coal, and particularly bituminous coal. As is well known, the mining of such coal takes place under highly adverse conditions, the solutions of which have been sought for many years. In the first place, the mining of the coal results in the floating through the air of very fine coal dust resulting occasionally in mine explosions usually with fatal results to miners. In the second place, the fine coal dust is inhaled by the miners, seriously affecting their health and resulting in a pulmonary disease commonly known as black lung.

SUMMARY OF THE INVENTION The invention in the present case preferably uses a coal mining unit similar to the one described and claimed in my copending application referred to, an elongated helix being rotated and fed laterally under the pressure of hydraulic rams, backed up by roof supports, into a vein of coal. The edge of the helix is provided at spaced points therealong with cutting elements projecting radially therefrom, these elements being formed of hardened carbon steel. The particular form and method of securing the cutting elements to the helix form no part per se of the present invention, these elements being known in the art. Means are provided for moving the helix vertically as it progresses through the vein of coal to cut throughout the height of such vein. Instead of employing the scavenger board of my prior application to form a coal-collecting trough, the present construction employs a board or partition which extends entirely from the floor to the roof of the mine and throughout the length of the helix. Instead of thus merely providing a collecting trough for the coal, the partition combines with the floor of the mine and the vein of coal to form a compartment, the bottom of which operates as a collecting trough, and the helix, when near the floor, acts as a conveying auger to convey the coal lengthwise of the helix for collection in a manner to be described.

The partition referred to confines coal dust to the compartment, thus preventing the spreading of the dust with the dangerous results referred to above. Means is provided for substantially eliminating the dust in the compartment. This is done in either of two ways. A vacuum pump has its inlet in communication with the compartment to evacuate air and consequently coal dust therefrom, and the air and coal dust thus evacuated pass through a separator to precipitate the coal dust. As a second means for accomplishing this result, the partition is provided with separate nozzles to substantially fill the compartment with a fine water mist to precipitate the coal dust, which falls to the coal in the bottom of the trough to be carried away by the conveying means.

In the prior art, mechanically mined coal is loaded by expensive loading apparatus. In the present construction, the coal is moved endwise of the trough directly to a conveying apparatus from which the coal is conveyed to one or more following conveying means to be discharged in due course. Where a vacuum pump is used for evacuating the compartment, the intake of the pump communicates with a portion of the conveying means which is housed, to carry off the fine coal dust from the stream of coal moving with the conveyor, and air is exhausted from the compartment through the conveying means to eliminate dust in the compartment.

In a preferred form of the invention, the vacuum pump is connected to the coal dust precipitator, and the latter is provided with a conveyor for moving wet coal therefrom back on to a portion of the main conveyor to be discharged with the main stream of conveyed coal.

The partition referred to has bodily connection with the helix and the hydraulic rams which advance the helix so as to be moved with the latter as the coal mining operation progresses. The top and bottom edges of the partition are so constructed as to slide over the floor and roof of the mine as the mining progresses, and means, preferably hydraulic in nature, is employed for maintaining the top and bottom of the partition in relatively snug engagement respectively with the roof and floor of the mine.

The invention further comprises a method of coal mining wherein the mining machine operates in a vein of coal within a confined space, and coal dust is continuously eliminated from such space. This elimination of coal dust may be accomplished, for example, by spraying water from the top of said confined space to pick up and precipitate dust particles, or air may be evacuated from said confined space to continuously carry off dust-laden air. The confined space may be elongated longitudinally of the adjacent vein of coal, and air may be ad-.

mitted to one end of said space while air is evacuated from the other end of said space.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic plan view of the preferred form of system;

FIG. 1 is an enlarged sectional view on line 2-2 of FIG. 1;

FIG. 3 is a fragmentary sectional view through the cutting auger shaft and associated elements looking in the same direction as FIG. 2;

FIG. 4 is a detail section on line 4-4 of FIG. 3;

FIG. 5 is a transverse vertical sectional view through the partition wall and associated elements;

FIG. 6 is a fragmentary section on line 66 of FIG. 5;

FIG. 7 is a face view of the partition wall, parts being broken away;

FIG. 8 is a fragmentary section on line 8-8 of FIG. I;

FIG. 9 is a section on line 9-9 of FIG. 8;

FIG. 10 is a section on line 10-10 of FIG. 9',

FIG. 11 is an end elevation of the driving motor and associated parts looking from the right-hand end of FIG. 9;

FIG. 12 is a section on line 12-12 of FIG. 1, parts being broken away;

FIG. 13 is a transverse section on line I3l3 of FIG. 1;

FIG. I4 is an enlarged fragmentary section on line 14I4 of FIG. 1;

FIG. 15 is a fragmentary sectional view of a modified form of the invention taken on line l5l5 of FIG. 7; and

FIG. 16 is a detail section on line l616 of FIG. 15.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, the numeral 10 designates a gallery of coal mine from which extend laterals 12 which communicate with the main gallery 14 leading to the entrance of the mine. The laterals 12 may be of substantial width and as much as 500 feet long and lying therebetween is a vein of coal 16.

In accordance with the usual practice the various galleries and laterals are provided with conventional hydraulically operated roof supports, a number of which are shown in FIG. 1 as being arranged in the gallery 10 and indicated as a whole by the numeral 17. Each of these roof supports is provided with an elongated usually rectangular horizontal roof-engaging element 18 FIGS. 1 and 2) arranged on the upper end of an hydraulic piston 20 vertically movable in a cylinder 22 to which hydraulic pressure is supplied through a pipe or hose 24. The member 18 engages the roof 26 of the mine, while the base of the cylinder 22 seats solidly upon the floor 28. The admission of hydraulic pressure into the cylinder 22 effectively supports and prevents the collapse of the roof 26.

One row of the roof supports is shown in FIG. 1, and these will be supplemented by additional roof supports as the mining operation progresses. For this purpose, each cylinder 22 is surrounded by a collar 30 pivoted as at 32 to an hydraulic ram 34 connected to the next adjacent roof support 17 for a purpose to be described.

The vein of coal 16 is shown in FIG. 2 and the coal is cut by a helix 36 which serves both as a mining device and as an auger conveyor to convey mined coal longitudinally of the helix as described below. The edge of the helix 36 is provided at spaced points therealong with cutting elements 38 in the form of hard carbon steel, the specific structure of which and the means for attaching them to the helix 36 are well known and form per se no part of the present invention. The helix 36 includes an axial shaft 40. While the helix is quite long, it may be made in separable sections shown in my copending application referred to above and forms per se no part of the present invention.

At the side of the helix opposite the vein of coal is arranged a partition 42 extending from the floor to the ceiling of the gallery and forming with the roof and ceiling and with the vein of coal 16 a compartment 44 in which the helix 36 operates. This compartment and the partition 42 are extremely important in accomplishing the results of the present invention.

The partition 42 is shown in detail in FIGS. 5, 6 and 7 of the drawings. This partition comprises a center section 45 formed of a metallic shell 46 and a filler 48 which may be made of wood, compressed board or any other suitable material to maintain the sides of the shell 46 planifoirm for a purpose which will become apparent. The upper endsof the center section 45 is vertically slidable into an upper section 50 comprising spaced sidewalls 52 preferably closed at their ends and provided at the top thereof with an arcuate skid plate 54en- 'gageable against the roof 26. The lower end of the center section 45 extends into a bottompartition section 56 comprising spaced walls 58 preferably closed at their ends and provided at the bottom thereof with an arcuate skid plate 60 slidable over the mine floor 28. The center section 45 has a sliding fit with the top and

bottom sections

50 and 56 as will be apparent.

One purpose of the wall is to seal the compartment 44 against the leakage of fine coal dust into the gallery 10. Since in performing any mining operation there will be some variation in the surfaces of the roof 26 and floor 28, the

skid plates

54 and 60 are maintained in snug engagement respectively with the ceiling 26 and floor 28 by the means shown in FIGS.

5, 6 and 7. To the center section 45 is secured a plurality of hydraulic cylinders 62, vertically arranged and provided with upper and lower pistons 64 and 66 connected to the ends of

piston rods

68 and 70, respectively. The rod 68 of each cylinder 62 is connected by a plate 72 to the upper partition section 50 and each lower rod 70 is similarly connected as at 72 to the lower partition section 56.

The chamber 74 between the pistons 64 and 66 is supplied with hydraulic fluid through a pipe or hose 76 leading from a pressure-reducing valve 78 supplied with pressure from a source through a pipe 80. The pressurereducing valve 78 is. intended to maintain a constant pressure in the chamber 74. However, variations in the surfaces of the roof and ceiling of the mine will sometimes cause relative movement of the pistons 64 toward each other, thus tending to compress hydraulic fluid in the chamber 74. This chamber is provided with a relief pipe 82 leading to a spring-loaded check valve 84 connected to a return line 86 leading to the source of hydraulic pressure. The valve 84 is set to maintain in the chamber 74 the pressure predetermined by the reducing valve 78. Any tendency for pressure to increase for the reasons stated in the chamber 74 relieves hydraulic fluid from the chamber 74 to maintain the constant pressure tending to maintain the

skid plates

54 and 60 in engagement respectively with the roof and floor of the mine. Upon any tendency for the pistons 64 to move apart due to surface variations in the ceiling and floor of the mine, pressure fluid will be supplied through the pipe 76 to the chamber 24 to maintain the desired pressure therein.

The partition 42 usually will be quite long and accordingly it is necessary that the partition be made up of separable and connectable sections. The partition is thus vertically and transversely separated along lines 88 at spaced points, for example, l0 feet apart, throughout the length of the partition. The plates 52 of the upper section 50 are flanged as at 90 and bolted together as at 92. The plates 58 of the bottom section 56 are similarly flanged as at 94 and bolted together as at 96. Similar flanges are formed on the center section 45 as at 98 in alignment with the

flanges

90 and 94. However, the upper and lower extremities of the flanges 98 are bolted together as at 100. The flanges 98 have their upper and lower extremities terminating in spaced relation to the adjacent edges of the upper lower sections as shown in FIG. 7 to provide for relative vertical movement of the sections incident to variations in the surfaces of the ceiling and floor of the mine. One of the hydraulic cylinders 62 is preferably arranged adjacent each end of each section of the partition to relatively distribute the vertical forces tending to move the top and

bottom sections

50 and 56 respectively upwardly and downwardly.

Referring to FIGS. 3 and 4, it will be noted that the helix 36 is interrupted at spaced intervals as at 102 to provide spaces for the reception of bearings I04 carried by arms 106 secured to the center section 45 of the partition as at 108. At the other side of such center section, a plate 110 is secured thereto, if

desired, by the same bolts which secure each bearing in position. Each plate 110 is carried by the end of a piston rod 112 extending into an hydraulic ram cylinder 114 (FIGS. 2, 3 and 4) and provided at its inner end with a piston 1 16. The ends of each hydraulic cylinder are provided with

hydraulic connections

118 and 120, and the left-hand end of each hydraulic cylinder 114 as viewed in FIG. 2 is pivotally connected as at 122 to one of the bands 30.

Above each hydraulic cylinder 114 is arranged a substantially vertical hydraulic cylinder 124 having a piston I26 therein, the piston rod 128 of whichis pivotally connected as at 130 to the associated ram cylinder 114. The upper end of each cylinder 124 is pivotally connected as at 132 to the adjacent roof support plate 18. Hydraulic fluid is admitted to and relieved from the opposite ends of each cylinder 124 respectively through

lines

134 and 136. Each ram cylinder 124, with pressure in the lower end thereof, supports the center partition section 45, the associated bearing 104 and the adjacent portion of the helix 36. Variation in pressures simultaneously in the upper and lower ends of the ram cylinders 124 effects vertical movement of the center section 45 of the partition and vertical movement of the helix to cut throughout the height of the vein 16 of coal.

In the present embodiment of the invention, the compartment 44 is shown as being open at one end as at (FIG. I while the opposite end of the apparatus is provided with a driving motor for the helix. Referring to FIGS. 1 and 8 to 11, inclusive, the numeral 142 designates a drive motor for the helix having embodied therewith a speed-reducing gearing 144, the output shaft 146 of which is coupled in any suitable manner to the shaft 40 of the helix. The output shaft 146 extends through a packing gland and bearing 148 to be coupled to the shaft 40, and the shaft 146 extends through a vertical wall 150 forming an end closure for the compartment 44. Thus the right-hand end of the compartment 44 as viewed in FIGS. 1, 8 and 9 is closed to the gallery 10 and lateral 12. The gallery 10 is cut through the vein of coal, one extremity 152 of which forms one wall of the gallery 12. Along this wall lies conveying means indicated as a whole by the numeral 152. This conveying means comprises an elongated housing 154 of rectangular section (FIG. 8) having its right-hand extremity in FIG. 10, as indicated by the numeral 156, opening into the compartment 44. The back of the compartment 44 in FIG. 9 is closed by the partition 42 while the end of the compartment is closed by the board 150. At the front thereof, the compartment is closed by a board 155 extending from the vein of coal 16 to the board 150 and fitted around the conveyor housing 154 as shown in FIG. 8. Bothboards 150 and S extend upwardly to the ceiling 26 to close the adjacent end of the compartment 44.

Adjacent the partition 42 and supported with respect thereto is a pulley 158 around which passes a conveyor belt 160 extending through the housing 154. From the compartment 44, both runs of the belt 160 slope slightly upwardly, and thence over pulleys 162 (FIG. 12). The runs of the belt then extend horizontally and pass around a pulley 164 supported by the housing 154.

This housing 154 telescopes into a second housing 166 forming part of the conveying means and in which is arranged a conveyor belt 168 passes around a pulley 170 adjacent the extremity of the housing 154. At its opposite end, the conveyor 168 passes around a pulley 172 rotatable in any suitable manner. The

conveyor housings

154 and 166 have been shown in FIG. 12 as being fully extended, which is the condition at the time the mining of the vein of coal 16 starts from the position of the helix 36 in FIG. 12. The housing 166 may terminate at the point 174 and is provided therein with a flap valve 176 to largely prevent the flow of air through the housing 166. The belt 168 extends substantially entirely across the housing 174, and the lower run of the belt 168 may pass over a flexible seal 178 secured to the bottom of the housing 166. The

seals

176 and 178 may be formed of rubber or any other flexible material and cooperate to prevent a rapid flow of air into the compartment 44 under conditions to be described.

Referring to FIGS. 1, l2 and 13, the sidewall of the housing 154 opposite the wall of coal is provided with an air exhaust opening 180 communicating with a duct 182 which turns as at 184 to extend parallel to the conveying means, that is, longitudinally through the gallery 12. After turning as at 184, the duct 182 slopes upwardly as at 186 (FIG. 10), then horizontally as at 188, and then downwardly at an angle as at 190. The duct 182 then communicates as at 192 with a casing 194 containing therein a body of water 196 which seeks its level in the sloping portion 190 of the duct 182. The raised portion 188 of the duct 182 is provided to prevent the water 196 from flowing to the inlet end of the duct and thence into the conveyor means.

The top of the casing 194 communicates as at 198 with a duct 200 leading to air exhaust pump 202. This pump exhausts air from the chamber 204 in the top of the casing 194, thus inducing the flow of air through duct 182 into the water body 196 to collect and precipitate coal dust and particles therein.

At the right side of the housing 194 (FIG. 14) an openended duct 206 communicates with the housing 194 and extends upwardly at an angle therefrom. A conveyor belt 208 extends through the duct 206 and passes around a pulley 210 at the far side of the housing 194 relative to the duct 206. Adjacent the outlet of the duct 206, the runs of the conveyor belt 208 pass around idler pulleys 212. The coal dust and particles precipitated in the water 196 is carried by the belt 208 (FIGS. 1 and 14) and discharged to a short transverse conveyor 214 which, in turn, discharges the wet coal onto the conveyor belt 168. The material on the latter belt is then discharged onto a belt 216 which carries the coal through the gallery 14 to be loaded on cars.

As previously stated, the hydraulic rams 124 support the associated rams 114, the piston rods 112 of which support the partition section and the shaft 40 of the helix, and provide upward and downward movement of the latter. The rams 1 14 are adapted to feed the helix laterally into the vein of coal to effect the progress of the mining operation. Obviously, it is necessary to support the motor 142 for similar vertical movement and for lateral movement with the helix as the mining operation progresses. To this end, the roof support adjacent the motor 142 (FIGS. 8, 9 and 1 1) is provided with an hydraulic ram 114 and a vertical ram 124 identical with those described above. The piston of the ram 114 adjacent the motor, however, is provided with a piston rod 218 having mounted on its end a yoke 220 engaging trunnions 222 carried by the housing of the motor as shown in FIGS. 9 andll. Thus it will be apparent that the

rams

114 and 124 associated with the motor 142 will be operated simultaneously with the remaining corresponding rams for imparting bodily movement to the motor 142 corresponding to movement imparted to the helix 36.

The means described for gathering coal dust by drawing air from the compartment 44 is preferred. However, the means shown in FIGS. 15 and 16 may be employed. The partition 42 may be provided at spaced points therealong near the top thereof with water pipes 224 projecting therethrough and provided on the compartment side of the partition with downwardly angled spray nozzles 226 which are preferably fan shaped as shown in FIG. 15 to spread the spray from the nozzles horizontally. A constant time spray from these nozzles will precipitate the fine coal dust in the compartment so that it will settle with the solid coal in the bottom of the compartment and be carried away by the conveying means.

OPERATION The apparatus will be setup as indicated in FIG. 1, the roof supports having been placed in position as the gallery 10 was excavated. It is assumed that all of the material between the floor and ceiling level and between the

galleries

10 and 14 and laterals 12 constitutes a relatively thick vein of coal. The sections of the helix 36 are connected together and connected to the center sections of the partitions 42 as shown in FIG. I, and the motor 142 will be supported in the yoke 220 as shown in FIGS. 9 and 11.

Hydraulic pressure is admitted to the lower ends of the cylinders 124 to support the helix and section 45, whereupon, with the motor 142 operating to rotate the helix, hydraulic pressure willbe admitted through pipes 118 into the left-hand ends of the cylinders 114 as viewed in FIG. 2. Thus a constant hydraulic pressure will be delivered laterally to the helix as it is rotating, causing the cutting elements 38 to dig into the vein of coal. When the digging has progressed, for example, as indicated in FIG. 2, pressure may be released from the lower chambers of the cylinders 124 and pressure supplied to the lower ends of these cylinders to move the center partition section 45 upwardly together with the helix to cut the upper portion of the vein of coal. It will be understood that all of the feed cylinders 114 for the helix are supplied with hydraulic pressure from a master control valve, and the same is true of the supporting rams 124. Operation of the ram cylinders 124 is reversed to cut to the bottom of the vein of coal 16.

In the starting of the apparatus there will be but one row of the roof supports available because of the limited width of the gallery in which the mining operation takes place, as shown in FIG. 1. When the ram pistons 116 have been fed to the right in FIG. 2 to their limits of movement, pressure will be relieved from the bottoms of the rams 116 one at a time, whereupon hydraulic pressure will be admitted to the corresponding cylinder 114. Since this operation, as stated, takes place with one ram cylinder 114 at a time, the remaining rams 114 will hold the partition 42 against movement. The admission of pressure through the pipe of one ram, therefore, will move the ram cylinder to the right in FIG. 2, thus similarly shifting the corresponding roof support 16. After one of the roof supports 16 has been moved to the right in FIG. 2, hydraulic pressure will be admitted to the lower end of such ram to seat the roof-supporting element 18 solidly against the roof. This operation is carried out by operation of successive rams and roof supports, and when all have been moved, the mining operation may be resumed.

In normal operation, as previously stated, a master control valve will control the admission and release of fluid pressure from the ends of the rams. For the purpose of moving the roof supports in the manner stated, however, individual valves will control the admission of fluid to the ram cylinders 114 to effeet individual movement thereof. This operation progresses repeatedly until the coal has been mined a sufficient distance so that, with the attendant movement of the roof supports, space will be provided behind such supports for the setting up of a further line of roof supports. This second line of supports will be identical with that shown in FIG. 2, and the cylinders thereof will be connnected to the first line of roof supports by the rams 34. Thereafter, when it is necessary to advance the first lineof roof supports, hydraulic pressure in the bottoms of the cylinders thereof all may be relieved simultaneously and all of the rams 34 energized to move the first line of roof supports to the right in FIG. 2 so that the mining operation can be continued.

The partition 42, as stated, will be made up of a plurality of sections bolted together, which obviously is necessary from a practical standpoint. For the purpose of the description of the invention herein, it may be considered that the partition is a unitary structure. This structure fills the space from the floor 28 to the ceiling 26, as shown in FIG. 5, and the partition thus prevents the admission of air into the compartment 44 from the gallery 10. The maintenance of a predetermined relatively low hydraulic pressure in the chamber 74 (FIG. 5) maintains the

skid plates

54 and 60, respectively, in engagement with the roof 26 and floor 28. Since the surfaces of the floor and roof will be somewhat wavey, there will be times when the overall height of the partition will increase, thus expanding the capacity of the chamber 74. The pressure in the chamber 74, however, will be maintained by hydraulic pressure supplied from the pressure-reducing valve 78. If the

skid plates

54 and 60 move relatively toward each other to reduce the capacity of the chamber 74, increased pressure therein is prevented by the opening of the check valve 84, which maintains the desired predetermined pressure in the chamber 74.

Referring to FIG. 1 it will be noted that the left-hand end of the compartment 44 is open to the flow of air thereinto. All remaining portions of the compartment 44 are closed to the admission of air. At opposite sides of the helix the vein of coal 16 bars the admission of air to any appreciable extent at one side of the helix, while the partition 42 bars the admission of air from the other side of the helix. Referring to FIG. 9, it will be seen that the board 150 closes the right-hand end of the compartment 44, this board extending from the floor to the ceiling as shown in FIG. 8. At the conveyor side of the compartment 44 the board 155 prevents the admission of air.

The pump 202 (FIG. 1) exhausts air from the right-hand end of the compartment 44 so rapidly that all dust will be moved to the right through the compartment 44 in FIG. 1, and will be withdrawn from this compartment through the interior of the conveyor housing 154. Thus air, laden with coal dust,

will flow out of the opening 180 into the duct 182, the opening.

180 being positioned with respect to the length of the conveyor housing as shown in FIG. 12. Since the remote end of the conveyor housing 166 is open, the flap valve 176 and seal 178 function to prevent the relatively rapid admission of air to the right in FIG. 12, thus maintaining a proper flow of air through compartment 44.

Air flowing into the duct 182 (FIGS. 1 and 14) flows upwardly through the raised portion 188 of the duct, thence beneath the surface of the water to bubble up through the water in the separator. 194 and then exhausted through the duct 200. The dust in the air will be picked up and precipitated by the body of water 196 and will be carried by the conveyor 208 to the transverse conveyor 214, the wet coal dust being deposited on the conveyor 168 and then carried together with the main body of coal to the cars on conveyor 216.

The roof support associated with the motor 142 in FIG. 8 and the rams associated therewith, identical with the

rams

114 and 124, are operated simultaneously with such rams so that when the helix is raised and lowered, the same operation takes place with respect to the motor 142. Similarly, when the rams 114 connected to the helix are advanced to move the cutting helix to the right in FIG. 2, similar movement is imparted to the motor 142 by its ram 1 l4.

The boards and (FIG. 9) are secured to the partition 42 and when the latter advances to feed the helix into the vein of coal, movement also is imparted to the boards referred to and to the conveyor 152 (FIG. 12). The housing for this conveyor telescopes with respect to the housing for the conveyor 168, and accordingly slides thereinto as the helix is advanced in its cutting operation. The lower run of the conveyor belt (FIG. 12) slides over the upper run of the belt 168 in such operation.

In practice, parts of the housing for the conveyor 168 are removable. When the housing for the belt 160 advances to a predetermined point, housing parts for the conveyor 168 are removed, the housing for the belt 168 is moved to the left in FIG. 12, and sections of the belt 168 are removed to shorten it.

In view of the foregoing, it will be apparent that while certain operations are necessary which interrupt the mining operation for short periods of time, such as the movement of the roof supports, the helix, which is relatively long, cuts constantly into the vein of coal. Accordingly, the mining operation takes place much more rapidly than is possible with present types of apparatus. It also will be apparent that the exhausting of air from the compartment 44 prevents any spreading through the mine of dust-laden air. This is highly advantageous since it prevents dust explosions and prevents the miners from suffering from a disease commonly known as black lung.

The use of the air exhausting means is preferred. Since fresh air is being constantly drawn into the open end 140 of the compartment 44, this air necessarily will cause a flow of air from the exterior of the mine, thus greatly assistingin ventilating the mine. However, a more economical setup for eliminating dust in the mine may be employed as shown in FIGS. 15 and 16. Fine spray-shaped mists may be forced into the compartment 44 to gather the dust and precipitate it to the bottom of the compartment 44.

Among the disadvantages of prior constructions is the difficulty and expense involved in conveying the mined coal from the points at which the miningtakes place. With the present construction, the helix is pitched in thesame direction from end to end. Thus coal falling into the bottom of the compartment will be moved by the helix, acting as an auger conveyor, to the right-hand end of the compartment 44 as viewed in FIG. 9. Coal is thus caused to be forced onto the upper run of the conveyor 160 to be automatically carried to the conveyor 168 and thence to conveyor 216 to be constantly moved to a point adjacent the loading cars. Thus the costs and labor normally involved in the conveying from the mine of the mined coal is greatly reduced.

The apparatus carries out the method outlined above. The actual coal mining operation takes place in a confined space represented by the compartment 44, and obviously the coal mining operation creates substantial dust throughout the operation. It is this dust, much of which is extremely fine, which creates the hazard of explosions and which dust is inhaled by the miners, thus causing so-called black lung. The method therefore comprises mining the coal in a confined space, and continuously eliminating dust during the mining operation. The dust, therefore, never escapes into the galleries.

of the mine to create the hazards referred to. The step of eliminating the dust from the confined space may be accomplished, for example, by spraying preferably a fine mist of water downwardly into the confined space from the upper part thereof, or it may be accomplished by exhausting air, together with dust suspended therein, from the confined space in a continuous operation during the mining operation. The confined space is preferably substantially elongated longitudinally of the vein of coal where the mining takes place, and dust is eliminated through the length of such confined space. Where the method involves the exhaustion of dust-laden air from the confined space, the air is exhausted, preferably from a given point in the space, and fresh air to allow for a flow of a current of air to the exhausting means is admitted at a point remote from the point at which the air is exhausted. More specifically,

the step of exhausting the air takes place by admitting air into one end of the elongated confined space and exhausting it from the other end of such space so that there is a constant flow of dust-laden air throughout the length of the confined space.

It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred examples of the same, and that various changes may be made in the shape, size and arrangement of the parts as do not depart from the spirit of the invention or the scope of the appended claims.

l claim:

1. In a coal mining machine, coal mining means adapted to be moved into a vein of coal to effect the mining thereof, a partition at the side of said coal mining means opposite the vein of coal, said partition extending from the floor to the roof of the mine to combine with the vein of coal and with the floor and roof to form a compartment said coal mining means operating completely within said compartment, said partition being formed of upper and lower vertically extensible sections, resilient biasing means for maintaining the upper edge of the upper said sections and the lower edge of the lower of said sections respectively in sliding engagement with the roof and floor of the mine, and means for constantly eliminating coal dust from said compartment.

2. Apparatus according to claim 1 wherein said partition includes a center section, said upper and lower sections being vertically extensibly connected to said center section, said means for maintaining said upper and lower sections in engagement respectively with the roof and floor of the mine comprising power means resiliently urging said upper and lower sections away from each other.

3. Apparatus according to claim 1 wherein said mining means comprises a helix having cutting elements fixed to the edge thereof at spaced points throughout its length, means for rotating said helix on a horizontal axis, and means for feeding said helix laterally into the vein of coal simultaneously with movement of said partition toward the vein of coal.

4. Apparatus according to claim 3 wherein said means for feeding said helix into the vein of coal is connected to said partition to move the latter simultaneously with said helix.

5. In a coal mining machine, coal mining means adapted to be moved into a vein of coal to effect the mining thereof, such means comprising a helix having cutting elements fixed to the edge thereof at spaced points throughout its length, means for rotating said helix on a horizontal axis, a partition arranged at the side of said coal mining means opposite the vein of coal, said partition extending from the floor to the roof of the mine to combine with the vein of coal and with the floor and roof to form a compartment, said compartment comprising upper and lower sections and a center section vertically telescopingly connected to said upper and lower sections, bearings carried by said center section and rotatably supporting said helix, said means for feeding said helix into the vein of coal comprising power means connected to said center section for transmitting a transverse force to move said partition laterally while feeding said helix laterally into the vein of coal, and means for constantly eliminating coal dust from said compartment.

6. Apparatus according to claim 5 wherein said power means comprises an hydraulic ram, and a vertical ram connected to said hydraulic ram to support the latter ram together with said center sections, said bearing and said helix, the controlling of the fluid in the ends of said vertical ram controlling vertical movement of said center section and said helix to vary the cutting action of said helix upwardly and downwardly in the vein of coal.

7. Apparatus according to claim 6 wherein said helix and said partition are horizontally elongated longitudinally of said helix to horizontally elongate said compartment, one end of said compartment being open for the admission of air thereto, and means for exhausting air from the other end of said compartment to carry off dust from said compartment with the exhausted air.

8. Apparatus according to claim 7 provided with means for closing said other end of said compartment and including an end board, a motor for driving the shaft of said helix through said end board, said means for closing said other end of said compartment being movable with said partition, said power means effecting movement of said helix into the vein of coal, and simultaneously similarly effecting movement of said partition, said closing means and said motor.

9. Apparatus according to claim 8 wherein said closing means is arranged beyond the end of the vein of coal in a gallery of the mine, and a conveyor projecting through said closing means and across said compartment, said helix being pitched to act as an auger conveyor to move coal lengthwise of said compartment onto said conveyor.

10. Apparatus according to claim 9 provided with housing in which said conveyor operates, said housing being open at one end to said compartment, said closing means including a board parallel to said compartment and fitted around said housing, said means for exhausting air from said compartment comprising a duct communicating with the interior of said housing.

1 1. Apparatus according to claim 10 wherein said means for exhausting air from said compartment further comprises a suction motor connected to said duct, and a dust precipitator arranged in said duct.

Claims

1. In a coal mining machine, coal mining means adapted to be moved into a vein of coal to effect the mining thereof, a partition at the side of said coal mining means opposite the vein of coal, said partition extendIng from the floor to the roof of the mine to combine with the vein of coal and with the floor and roof to form a compartment, said coal mining means operating completely within said compartment, said partition being formed of upper and lower vertically extensible sections, resilient biasing means for maintaining the upper edge of the upper of said sections and the lower edge of the lower of said sections respectively in sliding engagement with the roof and floor of the mine, and means for constantly eliminating coal dust from said compartment.

11. Apparatus according to claim 10 wherein said means for exhausting air from said compartment further comprises a suction motor connected to said duct, and a dust precipitator arranged in said duct.