US1353054A

US1353054A - Mining-machine

Info

Publication number: US1353054A
Application number: US818314A
Authority: US
Inventors: Nils D Levin
Original assignee: Jeffrey Manufacturing Co
Current assignee: Jeffrey Manufacturing Co
Priority date: 1914-02-12
Filing date: 1914-02-12
Publication date: 1920-09-14
Anticipated expiration: 1937-09-14

Description

N. D. LEVIN.

MINING MACHINE. APfLlcATfoN man ma. l2, 1914. nENEwED MN. 3. |920.

PatentedSept. 14, 1920.

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MINING MACHINE.

APPLICATION FILED FEB. l2, |914'. RENEWED 4IAII. 3. 1920.

Patented Sept. 14, 1920.

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MINING MACHINE.

APPucATmN FILED fz.12. 1914. RENEwED IAN. a. 1920.

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'tracks under its own power,

UNITED STATES PATENT OFFICE.

IILSl D. LEVIN,

COMPANY, 0F

OF COLUMBUS, OHIO, ASSIGNOR TO THE .TEFFREY MANUFACTURING COLUMBUS, OHIO, A CORPORATION OF OHIO.

MINING-MACHINE.

Specication of Letters Patent.

Application med February 12, 1914, Serial No. 818,314. Renewed January 3, 1920. Serial No. 349,350.

To all whom z't may concern.'

Be it known that I, NILs D. LEvIN, a citizen of the United States, residing at Columbus.7 in the county of Franklin and State of 0h10, have invented certain new and useful Improvements in Mining-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relates especially to mining machines of the class in which each is provided with its own track Wheels and is adapted to perform the cutting operations while supported on the said track wheels. Earlier machines devised by me for this general class of work were characterized by certain novel features, to wit, each had an elongated horizontally extending cutter arm mounted with a wi e bearing support directly over the wheel base so as to swing across the front of the machine from one side to the other of a supporting track to cut a horizontally extending kerf; each had means for adjusting the cutter arm vertically to vary the height of the kerf; and each was adapted to move over the mine so that it could travel into a mine room, approach the coal face over a centrally arran ed track and, while standing on the trac adjacent the face, by one continuous sweep of the cutter arm cut a horizontal kerf extending from rib to rib, thereupon moving under its own power to another room to repeat the cutting operation. But with these earlier machines it was impossible to cut a kerf at or near the floor of the mine, the vertical adjustment of y the cutter arm was effected somewhat inconveniently by hand, and it was necessary to move the cutter arm to a certain position before power could be applied to the track wheels to transport the machine.

The objects of my present invention are to provide a machine of the character of these earlier machines adapted to cut the kerf at or near the mine Hoor, having an improved mechanism for adjusting the cutter arm to different heights and inclinations and improved power rnechanism for driving the track wheels. Other objects will be apparent from the following description and claims.

The accompanying drawings show one embodiment of my invention, but I desire it to be understood that I do not limit myself to the exact form of construction which I have chosen for purposes of illustration.

0f the drawings1 Figure 1 is a plan view of the machine;

Fig. 2 is a side elevation of the machine;

Fig. 3 is a bottom view of the machine with parts broken away;

Fig. 4 is a sectional view upon an ena'rgel scale taken along the line 4--4 of ig. 5 is a sectional view upon an en larged scale taken along the line 5-5 of Fig. 1;

4 ig. G is a sectional view upon an enlarged scale taken along the line 6-6 of Fig. 1;

Fig. 7 is a sectional view upon an enlarged scale taken throu h the cutter frame along the line 7--7 of *ig. 3;

Fig. 8 is a detail view partly in section showing some of the elements of the feeding mechanism Fig. 9 is a fragmentary view of the brake and associated parts;

Fig. 10 is a fragmentary view partly in section of the parts shown in Fig. 9.

Referring to the drawings, 1 represents a steel plate to theedges of which are secured stlffening angles 2, and which is otherwise reinforced twproduce a rigid base frame. Upon this base frame is mounted the coal cutting mechanism. Fixed tothe underside of the plate 1 are suitable axle boxes 3 in which are journaled the axles 4 and 5, having wheels 6 adapted to travel along the rails of the mine tracks. The above described base frame together with the wheels.

constitute what will be termed the base of the entne apparatus. The axles 4: and 5 are connected together by the chain 7 which en Carried by the casting 10 are bearings 13,

14 and 15, in which is journaled a transverse shaft 16. At one end of the shaft 16 is mounted a sprocket wheel 17 in alinement with a similar sprocket wheel 18 on the axle 4. A chain 19 connects the two sprocket wheels. Formed as a part of the casting 10 is the lower half of a clutch and gear case 10a. The upper half of the clutch and gear case is formed by the casting 10". The casting 1()b carries bearings 20 and 21 in which is journaled a lon itudinal shaft 22 having at its forward en a flange shaft coupling 23 by which it is connected with the armature shaft of the motor 12. Secured to the shaft 22 is a worm 24 which meshes with the worm wheel 25, rotatably mounted on the shaft 16 to which it may be operatively connected by means of a clutch 26 of the well known friction disk type. This clutch 26 is shown in the drawin but need not be described in detail. The disk 2T is rovided for applying pressure to the dis s of the clutch and a ball bearing 28 is provided for carrying the pressure.

Rigidly mounted on the shaft 16, preferably between the

bearings

13 and 14, is a brake wheel 29 which is engaged by a friction band 30. One end of the brake band is adjustably secured to one arm of a bellcrank 31 and the other end is connected pivotall to a second arm of the same bellcran The bell-crank is secured to a short transverse rock shaft 33 mounted in

suitable bearings

32, 32 in the casting 10. The rock shaft 33 carries also an upstanding arm 34 which is adapted to be engaged by a cam 35 on the collar 36 loosely mounted on the shaft 16. The collar 36 can be moved by means of a hand lever 37, and it will be obvious that when the collar is moved, the cam 35 will enga the arm 34 to move it to tighten the braband 30. The casting 10 at points adjace the'bearing 14 is provided with a series of inclined teeth 38, and the collar 36 is provided with a series of oppositely inclined teeth 39 adapted to mesh with the teeth 38. The collar has formed upon it a flange 40, and between this flange and the plate 27 there is interposed a ball bearing 41. The surfaces of the

teeth

38 and 39 are so inclined that when the collar is rotated in a direction to release the brake, the collar is forced longitudinally of the shaft, and its motion is transmitted through the ball bearings 41 to the plate 27 to press together the disks of the clutch 26. When the collar is rotated in the other direction, the brake is applied and the clutch is released.

Preferably I provide at the rear of the truck a rotatable reel upon which can be wound an electric conductor cable for the supply of current to the motors of the mining machine and truck.' The free end of the cable is adapted to beconnected to a suitable source of electric current supply and the current passes through the cable and from it through suitable connections to the motors. Mechanism is provided for automatically winding up the cable on the reel when the truck is advanced toward the point of cable attachment, and when the truck is moving away from the point of cable attachment the reel is permitted to turn in the unwinding direction under frictional resistance. In the construction which I have indicated for pur oses of illustration, there are provided on t e truck extension 9, two reel supportin bars 42, 42, these being preferably angleaped in cross section. The vertical le s of these angles are provided with notc es 43 adapted to receive the lower ends of the reel frame 44 which is in the form of an inverted U. Mounted on the frame for rotation about a horizontal axis is a reel 45. Attached to the Worm wheel 25 to rotate with it, independently of the shaft 16, is a sleeve 46 upon which is loosely mounted a rope sheave 47 in alinement with' a rope sheave 48 attached to one side of the cable reel 45. An endless belt 49 passes over these two sheaves. The sheave 47 is loosely mounted on the sleeve 46 and is provided with clutch teeth 53 adapted to mesh with similar teeth on the clutch member 54 splined on the sleeve 46. T his' clutch member 54 can be slid along the sleeve into or out of operative position, and is frictionally held against accldental movement in either direction by the spring clip 55. The rope 49 serves not only to drive the cable reel when the clutch teeth 53 and 54 are 'engaged and when the worm Wheel 24 is rotated, but also serves to support the cable reel and reel frame in the position indicated in the drawings. 50 represents the electric conductor cable which is wound upon the reel. At 51 a suitable uide support is provided for controlling t e cable 50. 52 represents the flexible conductor extending between the cable reel and the motor 12 and the motor of the coal cuttin mechanism.

VThe conductor is of sufficient ength to give the required freedom of movement to the parts of the cutting mechanism.

Carried by the casting 11 are

bearings

56 and 57 in which is journaled a shaft 58 in alinement with the shaft 16. The shafts 16 and 58 can be connected by a jaw clutch, one member 59 of which is attached to the shaft 16 and the other member 60 of which is s lined to the shaft 58. Fixed to the other en of the shaft 58 is a bevel pinion 61, meshing with a bevel gear 62 which is attached to a vertical shaft 63 supported in

bearings

64 and 65 of the casting 11. The Shaft 63 carries at its lower end a sprocket wheel 66 for a` purpose which will be hereinafter setforth.

Mounted for longitudinal movement,` in

suitable apertures of the castings 10 and 11 is a shaft 67. To this shaft near one end is secured a shifting arm 68 adapted to engage with a clutch member 69, by which the sprocket wheel 17 is connected to the shaft 16. To the shaft 67 near its other end is secured a shifting arm 70 adapted to engage the clutch member 60. By means of the shaft the two clutch members can be simultaneously moved. The relation of this shaft 67 and the

arms

68 and 70 to the clutches is such that only one of these clutches may be enga ed at an one time and that both may be isengage if desired. The lever 71, attached t0 the shaft 67 between two

collars

71, and 71, serves as a convenient means for shifting these clutches into or out of operative position. A pin projecting from the lower side of the lever 71 engageable with suitable apertures 71b in the floor plate 9, serves to prevent accidental movement of the shaft and clutch members.

VSupported for vertical adjustment relative to the base plate 1 is a supporting frame in the form of an annular ring 72, adapted to support the coal cutting mechanism as will hereinafter appear. To this ring 72 are attached depending

brackets

73, 74, and 75, the lower ends of which are shaped to engage respectively with

upstanding guide members

76, 77 and 78, which are secured to the base plate 1 and which serve to prevent lateral movement of the ring and attached parts `relative to the truck. Secured to these depending brackets are screw nuts 79, which engage with

ad'usting screw shafts

80, 81 and 82, supporte at their top ends by bearing plates 83 attached to the upstanding guide members, and at their lower ends in step bearings formed in the bearing

brackets

84, 85 and 86 attached to the lower side of the base plate 1. The three sets of screw shafts and guide members constitute upright supports for the annular supportin frame, and the latter can be adjusted vertically in parallelism or angularly gy suitable rotation of the screw shafts. ounted for free rotation upon the

screw shafts

80, 81 and 82 are

sprocket wheels

87, 88 and 89 which are driven by the chain 90 from the s rocket wheel 66. Idler sprockets 91, 92 andp93 serve to ide the chain 90. The sprocket wheel 8 as shown in Fig. 4, has, formed upon its upper surface, clutch teeth 91 adapted to engage with similar teeth on the clutch member 92, splined to the screw shaft 80. The clutch member 92 is provided with a groove 93 in engagement with `an arm 94 attached to a vertical shaft 95 which extends through the floor plated, and is provided with a convenient handle 96 by which the movement of the clutch member 92 may be controlled. The shaft 95 carries a key 95a adapted to gage the inner surface of the ring.

support the shaft when the handle 96 is in the position shown. When the handle is turned the key 95 is brought into alinement with one of the notches 95", 95b in the plate 1 and the shaft can be raised or lowered.

The sprocket Wheels 88 and 89 are also provided with clutch teeth 97, as is shown in Fig. 5, which are adapted to engage with the teeth of the clutch members 98, splined to the

screw shafts

81 and 82. These clutch members 98 are provided with flanges 99 which extend so near to the edges of the floor plate 1 that they ma be lifted by the fingers of the operator. Idorizontally movable pins 100 are provided, by which these clutch members may be locked out of enga ement.

y the mechanism last described the power of the motor 12 may be applied to any, or all, of the adjusting screw shafts to effect the vertical adjustment of the ring 72 and with it of the cutting mechanism mounted thereon.

The top ends of the adjusting

screw shafts

80, 81 and 82 are formed square to admit of manual adjustment with a suitable wrench.

101 is a casting which forms the main frame of the coal cutting mechanism, and rests directly upon the upper edge of the ring 72, forming a turntable which is rotatable about the center of the ring. The turntable is held against horizontal displacement by means of rollers 102 which en- 103 is an electric motor secured to the under side of the turntable. This motor is connected with the main horizontal power shaft 104 by means of a pinion 103 on the motor shaft and a gear 104a on the shaft 104. A vertical power shaft 105 is operably connected with the shaft 104 by means of a bevel pinion 106 and a bevel gear 107.

108 is a horizontal shaft mounted in suitable bearings on the under side of the turntable. This shaft 108 carries a ratchet wheel 109 near its center. Pivotally mounted at each side of the ratchet wheel 109 are arms 110 between which there is pivotally mounted a pawl 111 which is normally held in engagement with the ratchet wheel by means of a spring 112. The arms 110 are oscillated about their pivotal axis by means of a link 113 which is connected therewith byV means of a knuckle joint 113` and is conA nected at its other end to the eccentric strap 114 of the eccentric 115 which is mounted on the shaft 105, being preferably formed as part of theA gear 10 116 is an arcuate finger mounted concentrically with the `ratchet wheel 109, and adapted to be oscillated about the axis of the wheel by means of the threaded rod 117 and the hand wheels 118. V119 is a second pawl normally engaging the ratchet wheel 109. This pawl is held in place by means of a spring 120.

In operation when the shaft 105, together with the eccentric 115, is being continuously rotated. oscillatory movement is given to the arms 110 and the pawl 111, which movement is transmitted to the shaft 108 by means 0i the ratchet wheel. The finger 116 serves to hold the pawl out of engagement with the ratchet wheel during part of its movement. By varying the position of the finger, the pawl may be held inoperative during a greater or lesser part of its movement, and the rate of rotation of the ratchet wheel and the shaft 10bl may be regulated. The pawl 119 serves to prevent retrograde movement of the ratchet wheel and shaft.

The shaft 108 carries at one end aworm 121 which meshes with a worm wheel 122 on a vertical shaft 123. The shaft 123 carries at its upper end '.1 winding drum 124 which is connected with the shaft. preferably by incans of a friction clutch 123L controlled by a hand wheel 125. 126 is a cable connected to the drum to be wound thereon. The end of this cable may. if desired, be secured, as shown in Fig. 1. to one or anotherof the vertical studs or holders 12T which are provided on the ring T2. Horizontal idler sheaves 128 are arranged in a circumferential series around the turntable. Irrcspective of which holder the end of the 'cable may be secured to. and irrespective of the position of the turntable, these sheaves 128 serve to guide the cable from the holder tangentially to the edge of the turntable.

It will now be apparent that when .the cable is connected to one of these` holders, and the winding drum caused to rotate in a windingr direction, the winding of the cable will cause the rotation of the turntable about the center of the ring.

Attached to the main frame casting 101 by a plurality of bolts 129 is a bracket 130 having a downward projecting extension 131 shaped to form

bearings

132 and 133 in which is journaled a vertical shaft 134. Fixed to the upper end of the shaft 134 is a sprocket wheel 135 connected by a chain 13G with the sprocket wheel 13T on the upper end of the ilain vertical power shaft 105 by which the shaft 134 is driven. The apertures in the bracket 130, through which the bolts 129 extend, are elongated to admit of longitudinal adjustment by the adjusting screw 138 to regulate the tension of the chain 130.

Formed at the lower end of the extensionv 131 is a foot 139 which carries the cutter arm 140. The cutter mechanism is of the well known type adapted to be fed side-wise into the coal, which is cut by cutting tools carried by a chain traveling in guide ways of the cutter arm. The foot 139 is adapted to side between the plates 141 and the bars 142 of the cutter frame to admit of longitudinal adjustment by the adjusting screw 143 to regulate the tension of the cutter chain 144. The cutter chain is driven by a sprocket wheel 145 fixed to the lower end of the shaft 134.

The operation of the machine is as follows. The track upon which the machine travels is positioned on the, center line of the mine room. The machine, propelled by the motor 12, enters the room With the cutter arm extending forward along the center line of the machine. When the machine has approached sufficiently near to the Working face the turntable is rotated to the right until the cutter arm is at right angles with the track. The machine is then moved forward until the distance from the coal face to the center of the turntable shall be equal to the length of the bracket 130 plus a suitable allowance for working clearance. By means of the vertical adjusting mechanism the coal cutting mechanism will then be lowered until the cutter arm is in the desired position to undercut the coal. After the machine has been secured in place, the motor 103 is started and the feed mechanism adjusted to cause the turntable to rotate to the left. As the cutter arm advances into the coal, the hand Wheel 118 may be manipulated to effect a variation of the rate of cutting according to the resistance offered by the coal, which will increase as the cutter approaches the center line of the room and decrease from the line to the finish.

lVhen the machine has cut an arc of 180 degrees, it is backed away from the coal face a sufficient distance to allow the cutting mechanism to be elevated into the traveling position; the cutter arm is preferably swung to the central position; and the machine is ready to travel under its own power to the next place of use.

\Vhile this device has been primarily designed to cut the coal at the bottom of the vein, it is apparent that it may be adjusted to cut at any elevation within the range of the vertical adjustment. The extension 131 of the bracket 130 may be of any desired length accordingr to the level of cutting desired, and I do not limit myself to a downward extending extension such as I have shown and described. By providing several brackets 130 of different sorts, with corresponding shafts 134, the machine may be adapted for cutting at an extremely Wide range of elevations.

Should it be desired to cut the coal from left to right, instead of from right to left as described, it is only necessary to reverse the bits 145 in the cutter chain 144, adjust the feed cable 126 to rotate the turntable in the desired direction` and reverse the direction of the motor 103 by means of the controller 146. In Fig. 1 I have shown by dotted lines the reversed arrangement of the cutter bits and a corresponding arrangement of the feed table 126.

It will be seen that by providing the ofi'` set power connection to the cutter mechanism through the shaft 134 I am enabled to cut a kerf at or below the lowermost plane of the wheels upon which the machine is supported. I believe myself to have been the first to provide a machine of the character herein set forth capable of cutting at this low level.

By means of the power mechanism connected to the

screws

80, 81 and 82, I am able to adjust the mechanism vertically; and by disengaging one or two of the clutches 91 and 97, 97 one side of the mechanism can be y raised or lowered' independently to change the angle of the cutter arm with respect to the horizontal. After the desired angle is obtained, all three of the clutches can be thrown in and the whole cutter mechanism can be raised or lowered in parallelism, the angle of the cutter arm being maintained constant.

It will be observed that the improved machine herein set forth embodies those novel features which I referred to at the outset as characterizing certain earlier machines devised by me; I do not claim herein the said features in their broader aspects as they are claimed in my co-pending applications Ser. No. 545,337, filed February 23, 1910, and Ser. No. 752,742 which is a division of my application Ser. No. 652,099, filed September 30, 1911.

What I claim is 1. In a mining machine of the class described, the combination of the wheeled track-guided truck having a bed frame held in rigid relationship to the wheel axis, a laterally swinging frame at the top of the machine comprising a horizontally widely extended approximately circular base frame element mounted on a fixed vertical axis and positioned directly above the bed frame, vertical column-like supports mounted upon and held in fixed relations to the bed frame, a horizontally widel extended ring-like frame element engaging with the extended base frame; arms extending downward from said ring-like element, a plurality ofvertical-acting adjusting devices stationary on the bed frame and each adapted to vertically move a part of the said ring-like support independently of the other part, an elongated horizontally extended cutter arm mounted to be fixed in horizontal planes; aA bracket extending downward from the base plate and supporting said cutter arm, a motor secured directly to the base plate, and power devices extending from said motor to the cutting apparatus.

2'. In a mming machine of the class described, the combination of a wheeled trackguided truck with a rigid bed frame, a horizontally widely extended laterally swinging base frame positioned at the top of the machine and directly above the bed frame and wheel base and mounted on a fixed vertical axis, an elongated horizon- `tally extended cutter arm, a chain carrying cutters and rotating around said arm, a vertically positioned and downward extending bracket rigidly and detachably secured to said widely extended base frame and secured to the cutter arm, a vertical shaft in the said bracket, a sprocket wheel at the up per end of said shaft, a sprocket wheel at the lower end'engaging the cutter chain, a motor supported on the swinging base independently of the bracket, and power transmitting devices extending from the motor to said upper sprocket wheel.

3. In a mining machine of the class described, the combination of a wheeled trackguided truck with' a vertically fixed bed frame, an elongated horizontally extended cutter arm mounted to be rigidly held in horizontal planes, a laterally swinging horizontally widely extended base frame at the top of the machine positioned over said bed frame and the wheel base. a plurality of column-like supports mounted rigidly on the base frame and held therewith against movement horizontally or vertically, a horizontally widely extended ring-like element engaging with the said horizontally extended base frame, brackets extending downward from said ring-like frame element and respectively engaging loosely with each of the said column-like supports, a motor on and swinging laterally with the base frame for actuating the cutters, a supplemental motor on the bed frame, and power devices actuated thereby for vertically adjusting the said brackets in the said column-like supports.

4. In a mining machine, the combination of a wheel supported base frame, a plurality of upright supports on the base frame, a supporting frame adjustably mounted on the upright supports, a cutting mechanism mounted on the supporting frame to swing with respect thereto about a vertical axis, mechanism adapted to operate optionally in connection with any or all of the uprlght supports to tip the supporting frame or raise and lower it in parallelism, and a motor to drive said mechanism.

5.- In a mining machine, the combination of a wheel supported base frame, a plurality of upright supports on the base frame, a supporting frame adjustably mounted on the upright supports, a cuttlng mechanism mounted on the supporting frame to swing with respect thereto about a vertical axis, power mechanism adapted to operate in connection with alloi' the upright supports simultaneously to raise and lower the supportlng frame, and means for rendering said mechanism inoperative with respect to any of the upright supports to permit the adjustment of the supporting frame on one or more of the upright supports independently of the other upright supports.

6. In a mining machine, the combination of a wheel supported rigid base frame adapted to run upon and be braced by the rails of a mine track, an elongated laterally swinging endless chain cutter apparatus carried by the base frame and projecting horizontally therefrom, supporting means between the base fratrie and the cutter apparatus comprising a plurality of upwardly extending supports mounted directly on the base frame at the angles of a horizontal polygon, said supports being stationary horizontally and vertically relatively to the wheels and the base frame, a non-rotary widely extended ring-like frame element carried by the said supports, a horizontal supporting frame adjustably mounted on the upright supports and in engagement with said ring-like support element and affording a widely extended bearing support for the swinging cutter apparatus directly above the wheel base of the base frame, means for adjusting di'erent parts of said horizontal frame vertically independently of the other parts thereof and power mechanism operable in connection with all of the upright supports simultaneously to raise and lower the supporting frame.

7. In a mining machine, the combination of a wheel supported rigid base frame adapted to run upon and be braced by the rails of a mine track, an elongated laterally swinging endless chain cutter apparatus carried by the base frame and projecting horizontally therefrom, supporting means between the base frame and the cutter apparatus comprising a plurality of rotatable screw shafts extending upward from the base frame at the angles of a horizontal polygon and secured against endwise movement and a horizontal supporting frame adjustably mounted on the screw shafts and affording a widely extended bearing support for the swinging cutter apparatus directly above the wheel base of the base frame, power transmitting devices to rotate the said screw shafts simultaneously to raise and lower the supporting frame and cutter apparatus and a second motor for actuating said power transmitting means.

8. In a mining machine, the combination of a wheel supported base frame, a plurality of upright supports thereon each comprising a rotatable screw shaft secured against endwise movement, a supporting frame adjustably mounted on the screw shafts, a horizontally oscillating cutter mechanism having an elongated cutter arm mounted on the supporting frame, and means for rotating optionally any or all of the screw shafts to incline the cutter mechanism or adjust it vertically in parallelism.

9. In a mining machine, the combination of a wheel supported rigid base frame adapted to run upon and be braced by the rails of a mine track, an elongated laterally swinging endless chain cutter apparatus carried by the base frame, and projecting horizontally therefrom, supporting means between the base frame and the cutter apparatus comprising a plurality of upright supports extending upward from and rigidly secured to the base frame at the angles of a horizontal polygon and a horizontal supporting frame adjustably mounted on the upright supports and affording a widely extended bearng support for the swinging cutter apparatus directly above the wheel base of the base frame, a motor on said horizontal supporting' frame for actuating the cutters, a second motor mounted on the base frame, and mechanism actuated thereby and adapted to operate in connection with all of the upright supports simultaneously to raise and lower the supporting frame and cutter ap aratus.

n testimony whereof, I affix my signature, in presence of two witnesses.

NILS D. LEVIN.

Witnesses:

E. L. HOPKINS, DUDLEY T. FISHER.