US1137224A - Grinding-mill. - Google Patents

Description

E. F. McCOOL.

GmNmNG MILL.l

APPLICATION FILED MAY 27. |912. 1,137,224. Patented Ap?. 27, 1915.

K M 4 SHEETSAHEET l.

u, if J5/062% E. F. McCOOL.

GRINDING MILL.

APPLICATION FILED MAY27.19|2.

1,137,224., Patented Apr. 27, 1915.

4 SHEETS-SHEET 2- @wi/imm@ 314042 moz www. l@

E. F. McCOOL.

GRINDING MILL.

APPLICATION FILED MAY21. |912.

1,137,224. Patentd Apr. 27, 1915.

4 SHEETS-SHEET 3- LF. MccooL. GRINDING MILL.

APPLICATION FILED MAY 27. |912.

5 m/f. mf M. m o m 1T e 0 m Wm a r. M @M pn i e ds d e4 r/N m w r a Q` P. W

marked thereon, which form 'cumstances described, Il

Urrrrnn .srrATEs PATENT oriucn. n

EDWARD l?. MoCOOL, 0F VICTOR, COLQBADO.

` @BINDING-mmh declare the following to be a full, clear, and

exact description of the invention, such'as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference a part of this specification.

l My invention relates to improvements inv grinding mills, my object being to provide an eiiicient construction of this class, in which provision is made for permitting a yielding movement in a longitudinal directionof the rotary member ofthe grinding head in order to prevent breakage or injury to the mechanism due to the entrance to the grinding jaws of a metal article or other foreign device which is too hard to be crushed. It sometimes happens that a metal tool, as a--wrench, is accidentally fed, with the ore, rock or other material to be ground, into the space between the'jaws or grinding members. f j

One of the objects of my present construction is to prevent injury to the machine due to an accident of thischaracter. While provision is Linade for ypermitting the rotary member of the hood lto move away from its relatively stationary member under the cirso provide means f rwhereby a clutch carried y the rotary hollow shaft is disconnected from the oper.- ating pulley from which power is transmittedto the hollow shaft through the instrumentality of the said clutch. Hence,` by

`virtue of my'improved constructionwhen the rotary grinding member yields to prevent injury to the apparatus, .the shaft which imparts movement to the grinding member is simultaneously Vdisconnected from the power which drives the machine stopped. v,

Provision is further made for producing an air-current within the housing inclosing the grinding members, whereby thepulveiized material, when reduced tothe proper whereby the moving parts" are quickly neness, isy removed from vthe housing, while particles which pass from between the grindv ing Amembers into the housingand which a're Specication of Letterav Patent.

not sufliciently ine for the purpose, will drop into a removable receptacle and may be introduced into ythe hopper for regrinding. The air-current is `made of-such strength and so regulated asto remove only such particles as have -been properly reduced. l

Having briefly outlined my improved'construction, I will proceed to describe the same 1n detail2 reference being made toy the accompanying drawing in which is illustrated an embodiment thereof.

In this drawing: Figure 1 is a longitudinal section taken through a grinding mill equipped with my improvements, parts, however, being shown in'elevation. Fig, 2 iS-a detail view of the friction-clutch' shown on a larger scale. Fig. 3 isa sectional view of the same. Fig. 4 is a .detail View of the l Patented Apr. 27, 1915. Application led May 27, 1912. Serial No. 668,907. I

the hollow shaft to an interiorly-located and y independently-movable operating shaft, the latter being eccentrically mounted in the hollow shaft and employed `for imparting. direct rotary movement to the movable mem'- ber of the grinding head. This view is obtained by looking inthe direction of arrow 4 Fig., 1. Fig. 5 is a section taken on the line 5-5 Fig. 1 looking toward the right or iii the direction of the arrow adjacent said line. Fig. 6 is a side elevation of the rear extremity of the machine or a view looking in the direction of arrow 6 Fig. 5. Fig. 7 is a front end elevation of the machine or a view looking in the direction of arrow '7 Fig. 1. Fig. 8 is a side elevation of the forward extremity' of Vthe machine.,

showing the .housing and the stationary j aw swung away from the movable jaw or grind- -ing member. Fig. 9 is a side elevatinof the same showing the'parts in the closed position. Fi 10 is asection taken on the line 10-10 Fig. 1 looking toward the left.

The same reference characters indicate the same parts in all. the views. Y

Let the numeral 5 designate a suitable vframe-work in which is'journaled a hollow shaft 6 upon which is splined va frictionmember-7 adapted to engage a power-pulley 8 which' is connected with a lmotor or other suitable ower not shown. As illustrated in thel rrawing, this clutch-member" is composed of a hub 9'splined upon the radially-disposed members 13 .provided with hollow shaft by. a key 10.' .Formed integrallw with this hub .is an open web 12 having recessesllrin whichare locatedsleeves 15 i which vare quite loose withinthe recesses and pivotally connected with the members 13 by means of pivot-pins 16, the said pins 'being' located near the inner .extremities of the vsaid sleeves topermit a slight rocking movement of the sleeves with their respective recesses. Appliedto each member 13 forward of its sleeve 15 is a rigid screw 17 located. near the outer extremity of the sleeve, which may beadjusted to regulate the swinging or tilting movement of the sleeve. On the opposite side of the sleeve and located directly across from the screw 17, is a spiral spring 18 which permits the sleeve to move or swing rearwardly on its pivot.

Threaded into the sleeve 15 is a screw 19 which is centrally provided with a part 20, fashioned to receive a wrench for adjusting purposes. This screw is threaded at both extremities, its outer portion -21 being 4threaded into a similar sleeve 22 which is Amovably mounted on a pivot-pin 23`located near its outer extremity, and threaded into the friction member 11 of the clutch which is movable independently of the body-member for releasing purposes. Aptplied to'this friction member in the rear o the sleeve 22 ,is a screw 24 which may be adjusted for limiting the movement `of the sleeve and the screw 19. l Opposite this screw 24 and located in a recess'also Iformed in the friction member, is a spiral spring 25, The friction member' which is connected with the sleeve 22 by the pivot-pin 23 as aforesaid, includes .-a shoe 26 composed of a metal 'member 27 and a member 28 preferably compos\ed of wood and connected with the me al memberby a suitable fastening device 29. Thev inner portionof 'each friction member 11 i's recessed to receive .the sleeve 22 which is loosely arranged therein for the same purpose as the similar arrangement of the sleeve 15 in the recess 14 of the body ofthe clutch. l

By virtue of the construction and arrangei ment of the clutch, as-heretofore described,

it will be understood that by moving the same' sligli'tly rearwardly on'the hollow shaft 6, eaclrscrew 19 willbe permitted to assume a position slightly inclined to the normal position. In other words, by a' slight movement of the clutchmember towardl the left (see Fig. 1) on the hollow lshaft .6, the inner extremity of each ofthe screws 1,9 will ,be caused to swing slightly rearwardly, while its outer extrem1ty will lag, whereby yeach screw 19 will be slightlytiltedvsoythat its inner extremity shall be farther rearward than its outer extremity.' This will result in moving each friction member 11 of the clutch'slightlj; inwardly whereby the clutch and consequently the 'shaft 6 is disconnected 65 from the power pulley.

i 6 is equipped with a crank-arm 30 whose The forward extremity of the hollow shaft outer extremity is provided with a wrist-pin 31.011 which a gear 32 is mounted to rotate. 4This gear travels in a relatively .large exteriorlyllocated stationary gear 33 and meshes with a relatively small gear 34 keyed to the operatin shaft 35 which is eccentrically mounte within the hollow shaft 6. In this manner rotary movement is imparted tothe operating shaft at, a different speed from that of the rotary shaft.

To the forward extremity of the operating shaft 35 is attached, as shown 'at 36, a hollow bracket 37, having a forwardlylocated elongated opening 38 adapted to receive a rectangular member 39 formed on a' rotary gnding member`40, the last named member in hollow, as shown at 41,- to receive the ace parts 42 of the hollow bracket on opposite sides'of the opening 38. v

in' the rearward direction suiliciently 'to bring the part 39 within the hollow or concavity 44 of the bracketin the rear of `the face members 42 of the bracket, and also in' the rear oflugs 45 which extend rearwardly and areseparated to receive the part 39 of the grinding-head when the latter is givenv a lquarter-revolution after inserting the part 39 withinthe opening 38 of thebracket. As soon as this is done, the part 39 (see Fig. 10)' may `move forwardly between the lugs 45, an as the operating shaft 35 is normally thrust forwardly, as hereinafter explained, while the bracket is normally thrust rearwardly; the grinding-member 40 will be securely heldA in' operative relation with the operating shaft. l

The bracket 37 is normally thrust rearwardly on the operating shaft by a vspiral spring 46 located within the hollow of the bracket and having its rearward extremity bearing against the rear end of the bracket on the inside, while its forward extremity engages a stop disk 47 applied to the forward extremity of the shaft 35. Theffor#` so lconstructed as to permit the grinding-p member a slight rocking movement on the bracket from a point 50 as a center. This movement will facilitate the grinding action of the apparatus.

The interior ortion 'of the grinding-member 40, where ltvengages the exterior por- 1erv ' tively stationary grinding-member'52, which is mounted in a housing 53 hinged as shown at 54 to a stationary member 55 carriedby a collar 56 surrounding the forward extremity of the hollow shaft. This housing is provided with an opening 57 through which the material to be ground may be'v introduced to the space between the grinding jaws through an opening"58. f

vso

The forward extremity of the hollow shaft 6 is equipped witha collar 59 which is made fast thereto and provided with fan-blades 60V which are located within the housing and surrounding the hollow bracket 37, being arranged to rotate within the space of the housing into which the ground material which has been reduced by the grinding members, must enter. This fan produces an air-currentI of suiicient strength to cause the properly ground material to be discharged fromthe housing through an opening 61 .formed in an outlet 62 which may be in .communication with a receptacle of any desired character for the pulverized material.

In the rear of the housing and formed integral with the stationary collar 56, isa hollow drum 63 provided with perforations 64,- communicating with the atmosphere. This drum also communicates with the interior of the housing in which the fan-blades 60 are located.- Hence, as the fan is rotated; within the housing, the suction produced thereby will draw air thereinto through`the perforations 64 ofthe hollow drum. The entrance of air through these vperforations maybe regulated at will by the adjustment jof a band 65 which is rotatably mounted on the drum and provided with perforations corresponding lto those in the drum. It will thusbe understood that .this band mayv be adjusted by meansoi:l a suitablehandle 66 so that its perforations may fully register with the perforations 64 of the drum, or only partly register therewithy as may bedesired and according to the volume of. air which may be requiredin order. to produce the necessary current for removing the pulverized material from the housing.

The rear extremity of the operating shaft 35 bears against a steel disk 67 whichiis lol cated withinan openingv 68 formed 4in the frame-work of the'machine andfinterlocked as shown at 69v with a non-rotatable block 70 which is longitudinallymovable within the opening .68 ofthe casing, but prevented from rotary action by means of a -key 71 secured@ ""to-theblock by a screw \72 and. slidable in a groove 73 formed in the casing-,outside of `of nuts 93 which are the circumference of the opening'68.

f cated in the rear. of the block 'is `a plunger 74 inwhich -is threaded a -screw 75 equipped at its rear extremity witha handwheel 76 exposed for manual operation.

This plunger 741is' recessed between its ex tremities as shown at 77 to receive togglelinks 78 which also engage recesses 79 formed in blocks 8() movable in hollow cylindrical members 81'1formed on the rear ex-- tremity of the frame and'being exteriorly open to receive interiorly-projecting tongues x82 formed on cross-heads-83'and 84 located respectively above and belowthe vertically movable blocks 80. These ltongues 82 are -centrally located on the cross-heads 83 and 84.4 The cross-head 83 is connected at. its opposite extremities-.with rods 85 by means of nuts 86 threadedxon the rods to engagementwith the top of the crosshead. The

lower extremities of these rods are 'connected with a cross-head 87 whose opposite extremities are slidable on rods 88, there being a pair ofV rods 88 at each end'of the crossfl" l, c Surrounding each rod ibetween a crosshead 8 9 and .the cross-head 87, are anumber of spiral .springs 90, intermediate crossheads 91 and 92'being employed in order to use a number of springs 90 instead of a single integral spiral spring extending between each pair'of crossheads 87 and 89, thus making it practicable to employ' relatively stili springs which are more easily manufactured ythan a single long spring' of corresponding tension.

It will be understood that'there is a pair, of rods 88 arranged on each side of the hollow cylindrical members 81, the two rods 88 of each pair being located lon opposite sides of the spiral springs. 90 and the rods '85 which are surrounded by the said springs.

The rods 88 of each pair are connected with one extremity of the cros -head 89 bv means plied to the rods above the cross-head. The opposite eX- trernities4 of these rods areconnected with the cross-head 84 by means of nuts 94 located -belowthe cross-head.'v All of the crossheads 87, 91 and 92 are freely'slidable onthe shown at 95 and pass through: openings formed in the opposite extremities of the cross-head 83 whereby-the cross-head is freelyvslidable on this rod extension., The

object of the extensions 95 is to guidethe` cross-heads and maintainlthem at all-A times inthe proper position,I and to prevent any tendency to get out of alinementv with the other cross-heads of the construction. It

will be observed that; with the exception of the rod extensions 95,- only two rods pass through the crossheads 83, namely the rods 85, one passing through each extremity of the cross-head and in the center thereof, the said rds being connected with the crosshead as heretofore explained, by nuts 86.

From the-foregoing description, it will be understood that whenever the grinding member 40 is thrust -rearwardly from the coperating grinding-member 52, whereby the operating shaft is thrust endwisein'a rearward direction, the blocks 80 'through the instrumentality of the toggle-links 78,v will be thrust outwardly from the plunger 74 and this action, through the medium of the tongues 82, will force the two crossheads'83 and 84 outwardly, the one moving upward and the other downward, whereby the. springs 90 are compressed. As soon, however, as the obstacle interposed between the grinding members has been removed, the springs will restore the grindingfmember 40 to its normal position with reference to the relatively stationary grinding-head 52.

As the lower cross-head 84 is moved downwardly by virtue of the operation hereinafter described, it acts upon a sort of bellcrank lever 96 which is connected by means of arod v97 with a lever 98 to automatically shift theclutch 7 towardthe left on the hollow shaft 6, a suflicient distance to release the clutch from the operating pulley 8, whereby the power which operates the machine is disconnected from the shaft 6 and its associated elements, thus stopping the machine. The bell-crank lever 96 is fulcrumed as shown at 99 on a stationary part j 100 of the frame-work. An arm 101 of this lever is acted on by the cross-head84, while al1/arm ..102 is connected as shown at 103 with one extremity of the rod 97, the opposite extremity of the last-namedl rod bemg.

connected as shown at 104 with the lower extremity of lthe. member 98, the' latter being fulcrumed onf'the frame-work as shown at l f u The upper arm ofthe lever 98 is forked, as shown at" 106, to straddle` the collar 9 of the clutch 7, the parts of this arm on oppositevsides of the collar being pivotally connected as Shown at 107 with a ring 108 loose on the collar 9, and engaging a circumferential groove 109 formed in "the collar. By virtue of this construction and arrangef ment, the clutch is slidably actuated on the hollow shaft 6- whenever the cross-head 84 is moved in either direction'.

Referring again to the housing 53, the latter is pivotally connected as shown at 110 with a lever-arm 111 which is pivotally connected as shown at 54fwith the bracket 55 heretofore? described.:l Intermediate the extremities of the lever-arm 111 is a recess v112 in which is ,seated/a' spiral spring 113, the said spring also Ibearing on the upper portion of the housing. The forward extremity of the" lever-arm 111 is providedy 'posite arm 123 being equipped with with a Aface 114 which is adapted, when the housing is swung. outwardly (see Fig. 8) to be engaged by a face 115 formed on' a lug 116 of the housing.

The housing is locked in place by means of a lever-like device 117 pivotally connected as .shown at118 with a stationary bracket 119 also connected with the collar 56 and the drum 63.-' This device v117 extends forwardly, from the pivot 118, and With its outer extremity is pivotally connected with a locking lever 120 fulcrumed on the device 117 as shown at 121. This locking lever is slightly angular in shape and is provided at one extremity with a hand-piece 122, its 0pa rounded bearing extremity 124 which is "provided with a screw-stem 125 threaded into the arm 123, whereby the part 124 is adjustable. v

The lower portion of thel housing 53 is provided with a lugl 126 which is provided with a curved recess 127 adapted to receive the extremity 124 o f the lever 120, when the housing is in the closed osition. In other words, after the housing lias been opened to the position shown in Fig. 8, in order to close it, it may be swung inwardly toward the rotary grinding-head to the dotted-line position in Fig. 8, after which, bythe manipulation yof the lever 120, the extremity 124 may be brought into engagement with the lug 126, and as the handle-extremity of the lever `is swung in the direction indicated bythe arrow in Fig. 8, the housing will be thrown to its closed position, the device 117 being at the same time raised, and the lever 120 moved to a position in alinement with the device 117, thus locking the housing in the closed position.

'From the foregoing description, the use and operation of my improved grinding millwill @e readily understood. Power is -delivered to the 'machine from a suitable source (not shown) through the medium of the pulley 8, which, when the machine is in position for use, is en aged in operative relation by the clutcl splined on the hollow shaft 6, as heretofore explained. Hence, as

the pulley is rotated, the shaft1 6 is also ro' tated, and motion is simultaneously imparted to the operating shaft 35 through themedium of the crank-arm 30, and the gears 32,

33 and 34: Hence, it will be understood that 'as the hollow shaft 6 is rotated, the

operating shaft l35 which is eccentrically mounted in the -hollow shaft will have an orbital travel with the hollow shaft independently of its rotary motion on its own axis. 40 isfnot only rotated forgrinding purposes, but isalso given in addition a lateral or slidingmovement simultaneously, rthus facilitating the vperformance of the grinding function.

Consequently, the grindingmember A:animee M.

.- Thematerial to be treated is introduced through the opening 57 of-the'housing'and passes thence through the opening 58 in the stationary jaw 52, into the space between the grinding jaws 40 and 52. As this material is groundto the necessary degree of fine'- ness, it escapes from between the jaws into the interior of the housing 53 and isdriven therefrom through the medium of a current of air produced by the fan-blades 60 `out of the housing through the opening 61, any

particles which are too large to be removed by the air-current dropping into a slidable 'receptacle 128 which" is supported by means of a casing129, connected with the lower part of the housing.

In the event that a substance too hard to be reduced b the grinding-members shall have been :fe thereto, the rotary grinding 20 member 40 will be thrust rearwardly, to-

gether with the operating shaft 35, and by virtue of the yielding capacity-of the springs 90 arranged in connection with the cross-- heads 83 and 84 heretofore described.

It must bdunderstood that-die grindidg I member is permitted a' slight' rocking -movement on the hollow-bracket 37 with which'it is connected. .This is permitted by virtue of the curvature of the inner surface 80 of the member 40 where it engages a corre` spondinglycurved surface '130'of the said bracket. y n

,The coil spring 113 acts on. the housing 53 in the rear lof the center: of the latter .35 and at faconsiderable distance from the livot 110, whereby, as/soon as the housing is unlocked by throwing the..v locking lever 120' t'ol the unlocked position, the spring acting omthe housing' will automatically throw 40 the latterto the open position approximately vas4 indicated by the dotted lines in'Fig.- 8. d

"As illustrated i' in the d-rawing, the stationary grindingmember V52 is secured to the housing by means of bolts 131. i

45. yIn order to 'notify the p'erscn'in charge of thema'chin'e that an article or foreign substanceof such character has passed between grinding members as to cause'the operat ingshaft 35`to move rearwardly and actuate the' clutch 47 to disengage the latter `from the power-pulley through the instrumentalityv of the connections'heretofore described, an electrical" signal imay be employed. (see Fig. 1). 4This signal' consists, fas illustrated in the drawing, of 'a bell `132 connected bymeans of' a wire1 133 f with a pole 134.- o a battery 135. The belll is also connectedby means f a wire `136 with 'a contact 137 mounted Non the. frame but insulated therefrom, as

shown at 138. From the -opposite"'pole 139 of thel battery, a" wire 140 lleads to a contact '141. fast. on the rod'97, 'but-insulated there- Afrom as' shdwn atf'142. The twocontacts thaving-their axes atright angles .to the axis' .a toggle connection between the blocks and 's to act on the in an endwise by 'the movement of the lever 96; in a direction 'to act upon the lever 98 to disengage the clutch from thepower pulley, the contact 141 will be brought into engagement with its operating contact 137, thus closing 1,0

-the battery circuit-and operating the bell It will be understood that any suitable,

electrically operated signal may be employed, whether audible, visual or both. v

Attention is called to the fact that in m improved construction the grinding or pu verizing. jaws are respectively convex and its movement on its own axis, and its move- T85 ment with fthe hollow. shaft due to its ec. centric mounting therein, whereby it travels in ani orbit simultaneously with its axial travel. Y

Having thus described my invention, what Iclaim is: 1 v

1. In an orev grinder, the combinationv oi" a grinding-member, a rotary shaft connected 1n operative relation with said member, spring-actuated cross-heads movable at 95 right angles to said shaft, andan operative connection between the said shaft and said cross-heads whereby the springs act to imy part an endwise thrust to the-shaft in the direction olf the grinding member. v2.l In an ore grinder, the combination of a grinding-member, 'an endwise movable rotary shaft connected in operative relation withv vsaid grinding member, coil springs 10.5 of vthe shaft, and an operative connection between said springs and the shaft to impart an endwise thrust vto the latter.

3. -Inan ore grinder, the combination of a grinding-member, an endwise -movable rotary shaft connected in operative relation with said grinding-member, fcoil springs having their axes at right angles-to the axis of the Shaft, and an'operativeiconnection between said springsl and the shaft to impart ,115 an endwise thrust to the latter, lcomprising blocks acted on by the sprin s and movable at right angles to the axis o the shaft, and

the shaft.A

4, The 'combination of a4 grinding-member, a vrotary endwise movable shaft connected inoperative relation with the grinding- I'niember, blocks movable at right angles to the axis-Tof the shaft, cross-heads acting on vthe blocks,- springs acting on the cross-heads, 'and ato le connection between the blocks ftheaft 'to cause the tension ofthe angles to the axis o the shaft, atoggle connection. between the said blocks and the shaft, cross-heads vactingl on the blocks,`

springs acting on the .cross-heads, a power pulley concentrically arranged with reference to the shaft but loose thereon, having a clutch splined onthe shaft and connecte in operative relation with the power pulley and an operative connection between one of -the said' cross-heads and .the clutch, whereby, as the cross-headsare thrust outwardly by the rearward movement of the shaft, the c utch is actuated to v disen age the shaft from the power influence o? the operating pulley, substantially as described.

6. In agrinder, the combination of an endwise-movable shaft, a grinding member connected in operative relation with one extremity of the shaft, blocks movable at right angles to the axis of the shaft, a toggle connection between the said blocks and the shaft, cross -heads acting on the` blocks, springs acting on the cross-heads, a power pulley concentrically arranged with reference to the shaft but loose thereon, a clutch splined on the shaft and connected in o erative relation with the power-pulley, an an operative connection between one of the said cross-heads and the clutch, whereby, as the cross-heads` are thrust outwardly. by the -rearward movement of the shaft, the clutch is actuated to disengage the shaft from theoperating pulley, said connection includin a lever having'one arm in engagement wit the operating cross-head, a second lever having one arm in engagement with the clutch, and a rod connecting the two levers.

7. Thefjcombination of a grinding-member, a rotatable endwise-movable shaft having one extremity engaging a grinding- I so shaft to member, a hollow shaftin which the-first named shaft is eccentrically mounted, an operating pulley loose on the hollow shaft,

a clutch splined on the hollow shaft and 4^ connected 1n operative relationwith thesaid pulley, a. gearing connection between the hollow shaft and the first named shaft, and anf operative connection between the rst 4naine shaft and the said'clutch, whereby, as the first named shaft is thrust rearwardly, the clutch is'actuated to disconnect it from the power-pulley for the purpose vset forth.

8. The combination of a grinding-member, a rotary endwise-movable shaft having one extremity in engagement with the inding-member, springs actin on the hold the lattei/ in yieldab e relation in an endwise direction with the grindingmember, means for applying rotary motion to the shaft, and an. operative connection to the rst named shaft, a housin fan 1n sal rounded end,- va socket adapted to iit said rounded end, a

vsubstantially as described.

9. In a grinder, thecombination of a ro-4 tary grinding head, a shaft connected in operative relation with said head to rotate the same, a, hollow shaft in which the first named shaft is eccentrically mounted, means for appl ing power to the hollow shaft, and

rounding the grinding member, fan lades located in the housing and connectedwith the hollow shaft whereby the fan blades are rotated when the machine is in operation, a stationary drum in communication with the housing and having openings communieating with the atmosphere whereby, as the fan blades are rotated, a current of air is produced within the housing of. suiiicient strength to'ex el the pulverized material through an ou et with which the housing is provided.

10. In a grinder, the combination with an end-wise movable shaft, of a grinding member supported upon said shaft, blocks mounted for movement at right anglesto said shaft, toggle connections between said blocks and shaft, sprin tending to 4force thesaid blocks inwar y, a power pulley concentrically arran ed with reference to the shaft but loose t ereon havinga clutch splined on the shaft and connected in operative relation with the ower pulley, and an operative connection tween one of said blocks 'and the clutch whereby as the blocks are thrust outwardly by the rearward movement of the shaft the c lutch is actuated lto disenga e the shaft from the power iniiuence o the pulley, substantially as described.

11. In an ore grindelya shaft, a grinding` Imember supported upon said shaft, means bearing upon said shaft tending normallly to thrust it yieldably forward, a powerp ley looselymounted upon said shaft and clutch acting normally to hold said shaft and pulley in operative position andmeans for automatically releasing said shaft under the influence of rearward pressure upon the same.

12. In a grinder, a casing, a grindingl member in the casing, means for imparting a planeta movement to said member, a

`casing, means for rotatin said fan about the center of revolution o said grinding member, said casing having a passage leadingftherefrom through which the grpd'uid material is adapted to be forced by sai an. y

ding disk having a bracket slidably mounted on said shaft and adapted `to engage said' disk and a spring 126` 13..In combination, a shaft having a tending to hold said bracket and disk in iiXed relation.

14. In combination, a shaft having a rounded end, a grinding disk havin a socket adaptedto .t said rounded en ,a iange upon the rear of said disk, a bracket slidably mounted upon said shaft, a iiange upon said bracket adapted to-bear against the forward side of the flange (upon the disk and yieldable means acting upon said bracket tending to force said flanges together, whereby the bracket and disk are held in fixed relation.

15. In an ore grinder, a shaft, a grinding member supported upon said shaft, means bearing upon said shaft and tending nor- 'mally' to thrust it yieldably forward, a

power pulley loosely mounted upon said shaft and a clutch vacting normally to hold said shaft and pulley in operative relation, and means for automatically releasing said shaft from the power pulley through the medium of the clutch, under the influence of rearward pressure upon the same.

In testimony whereof I aHix my signature in presence of two witnesses.

EDWARD F. MOCOOL. Witnesses:

M. J. ONEILL, WALTER POLE.

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