US1655499A - Adjustable plow for centrifugal grinding mills - Google Patents

Adjustable plow for centrifugal grinding mills Download PDF

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US1655499A
US1655499A US758635A US75863524A US1655499A US 1655499 A US1655499 A US 1655499A US 758635 A US758635 A US 758635A US 75863524 A US75863524 A US 75863524A US 1655499 A US1655499 A US 1655499A
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plow
arm
grinding
pan
axis
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US758635A
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William A Gibson
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BRADLEY PULVERIZER CO
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BRADLEY PULVERIZER CO
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B02CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02CCRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C15/00Disintegrating by milling members in the form of rollers or balls co-operating with rings or discs
    • B02C15/02Centrifugal pendulum-type mills

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  • I4 a a ⁇ nvenTor. WilliumA.Gibson Jan. 10, 1928.
  • This invention relates to improvementsin centrifugal grinding mills and the 'object thereof is to provide means for moreefiec tively delivering the material to be ground to the co-o'perating grinding members.
  • Centrifugal mills ofv this type comprise a grinding pan having an annular die therein, usually a plurality of centrifugally oper able grinding rolls co-operating with said annular die and a plowor plowsrotatable with said grinding roll or rolls and in ad- Vance thereof extending into the material to be ground andacting to deliver the material to; the co-operating grinding members.
  • the plows In grinding mill constructions of this type heretofore constructed the plows have been secured in a predetermined rigid position. It has been found that the plow actsidiiferently upon different materials, such as those having different specific gravity, or upon materials differing in fineness, and particularly with a very different action upon coarse material and relatively fine material which is frequently introduced into the mill for repulverization.
  • the object of the present invention is broadly to provide means for adjustably supporting the plow-to enable it to be se cured in various different positions of adjustment.
  • One of the objects of the invention is to provide means for securing the plow atdifferent distances toward and from thembottom of the pan.
  • Another object of the invention vide means for differing the inclination or tilt of the plow so that the face whichserves to project the material toward the co-operating grinding members may be more or less inclined.
  • a further object of the invention is to provide means for rotatably adjusting the plow about the axis of itssupport so that the position of the ploW maybe varied with respect to the radius of the annular grinding die.
  • he present invention comprises means for accomplishing all of these purposes as well as easily operable means for securing the various adjustments. r I
  • the invention is applicable to numerous usual types of grindi1ig mills,,it illustrated herein asembodied ina centrifugal grinding mill of, the general type illustrated in Patent No. 1,175,436, Grrifiin,grant-- is to pro- I ed'iMarch 14, 1916, and No. 1,473,341, Gibson and Needham, granted November 6,
  • FIG. 2 van enlarged detail front elevation of a plow-supporting arm and plow adjustably secured thereto embodyinga preferredform of theinvention, theplow-supporting arm being broken away;
  • Fig. 3 is a side elevation, of the same; and j j I Fig. is a view showing the plow-supporting arm in transversesect-ion and the plow andhthe means for securing the plow to said arm in elevation.
  • the base 2 is also provided with extonsions or bossesfli I whichreceigve the lower ends of preferably A-shaped standards 6; upon the upper ends of which are mounted saddles 7 which support a transverse girder 8 whichsustains the rotatingpertsof the mill.
  • the rotating members comprise afquill; shaft- 9 which is supported by a bevel gear 10 which rests upon the transverse girder 8 andis driven by a beveled pinion 11 upon a suitable driving shaft 12 j ournaled in bearings in the saddles 7
  • the quill shaft 9 is rotatably mounted upon astationary central shaft 13 the lower end of which is tapered andsuitably secured in a central boss 1 in; tegral with and extending upwardlyfrom the pan.
  • the shaft 13 has secured to it a carrier 15 of general cylindrical form, the
  • the base portion of the carrier is provided with downwardly and outwardly extending chutes 21 which deliver the material in proximity to the periphery of the pan and into the path of the crushing rolls.
  • the lower end of the quill shaft supports a horizontally disposed spider 22 which is made in sections to fit around and enclose the reduced lower end of the quill shaftwhich is provided with a rib 23 adapted to engage an annular recess in the spider and prevent the latter from longitudinal movement upon the quill shaft:
  • This spider serves to support the plow or plows which travel in the grinding chamber beneath the'path of the rolls and force the material in the grinding pan into the path of the rolls.
  • the object of the present invention is to provide means for ad justably supporting the plow in such a manner that it may be secured in any or all of the various positions of adjustment so that the most effective action of the plow may be obtained for the particular kind of material which is being treated in the mill.
  • the adjustments provided for by the present inven tion comprise, first, the bodily adjustment of the plow toward and from the bottom of the pan: second, a tilting adjustment by means of which the angular position of the face of the blade relative to its plane of movement may be varied; and, third, an adjustment about the axis of the plow support by means of which the angular relation of the blade to the radius of the annular die may be varied.
  • the spider is provided with one or preferably a series of downwardly and outwardly extending sockets 24: which may be of cylindrical form and in which the upper ends 25 of cylindrical plow-supporting arms 26 are mounted and secured in any suitable manner as by set screws 27, or other suitable means which will permit the arm tobe rotat'ably adjusted about its aXis in such a manner that the plow. may be adjusted angularly with respect to the radius of the annular die.
  • the plows may be secured to the lower ends of the arms 26 in any suitable manner to provide for other adjustments.
  • the plow comprises a flat inclined blade 28 to engage the material and an integral upwardly extending preferably flat member or web 29 which is secured to the arm 26 by a bolt 30 and is provided at its upper end with a laterally extending arm 31 which extends behind and across the rear edge of the arm 26.
  • a screw 32 seated in the arm 81 abuts against the rear edge of the arm and serves to retain the plow in adjusted position about the axis ofthebolt 30 as the engagement of the plow with, the material tends to rotate the plow about the axis of the bolt in aidirection which will force the end of the screw 32 against the rear edge of the arm Obviously by screwing up or unscrewing the screw 32 the plow may be tilted more or less relatively to the plane of its movement. By thus varying the angular position of the face of the plow the material may be projected upwardly at a greater or less angle.
  • the plow shall travel in paths at different distances from the bottom of the pan. This is accomplished by providing means by which the effective length of the plow-supporting arm may be varied. Means are provided in the present invention for producing this adjustment either separately or coincidentally with the tilting adjustment.
  • the plow may be adjusted longitudinally of the arm by unscrewing the not of the bolt and raising or lowering the position of the rib or in such a manner that it will inter-engage with selected ribs upon the arm 26 and thereupon setting up the bolt 30.
  • the rib 34 is concentric with the axis of the boltand the ribs 33 are complementary in curvature to the rib 3-1 the tilting adjustment above described can be made at the same time by setting up or withdrawing the screw 32 the desired amount.
  • the plow can be raised or lowered relatively to the pan so that it will engage more or less of the material in the pan; the plow may be tilted to adjusted positions to cause the material'to be projected upwardly to a greater or less 7 height and the plow may be adjusted about I ment of parts may be made within the spirit and scope of the following claims.
  • a centrifugal grinding mill comprising a pan, an annular die, a centrifugally operable grinding member therewith and a plow movable with said grinding member, means for supporting said plow including adjustable means for securing said plow in different vertically tilted positions relatively to the plane of said pan about an axis substantially radial to the path of 'i'novement of the Pl0 ⁇ 2.
  • a grinding mill comprising a pan,
  • annular die a plurality of co-operatingv grinding members rotatable about a common central axis co-operating with'said die, aplow-supporting arm rotatable about said central axis, a plow, interengaging members upon said plow and said arm and means pivotally connecting said plow to said arm.
  • a grinding mill comprising a pan, an annular die, a plurality of co-operating grinding members rotatable about a common central axis co-operating with said die, a plow-supporting arm rotatable about said central axis, a plow, complementary faces upon said plow and arm having interengaging members and pivotal means for clamping said plow to said arm operable to per-' mit adjustment of said plow longitudinally of said arm and also rotatably about said pivotal connection.
  • a grinding mill comprising a sta tionary' grinding member and a plurality of co-operat-ing grinding members rotatable about a common central axis, a plow-supporting member also rotatable about said central axis, a plow, complementary faces upon said plow and said arm, one of said co-operating plow-supporting arm.
  • a clamping bolt for securing said plow to said arm concentric with respect to said ribs and extending substantially radial to the path of movement of said plow and adjustable means for retaining said plow in a predetermined position of ad ustment about the axis of said .clamping bolt.
  • a grinding mill comprising a stationary grinding member and a plurality of co-operating grinding members] rotatable about a common central axis, a plow-supporting" member also rotatable about said central axis, a plow, complementary faces upon said plow and said arm, one of said faces having a plurality of arcuate ribs and the other face having a complementary rib, means for adjustably clamping said faces together including a bolt in one of said members concentric with its arcuate rib and extending substantially radial to the path of movement of he plow and seated in a slot 7 in the other member extending substantially in the direction of the axis of such member and adjustable means for retaining said -plow in a predetermined position of adjustment about the axis of said bolt.
  • a centrifugal grinding min comprising a grinding pan having a die, a central upright shaft, a quill shaft rotatable upon said upright shaft having a carrier supporting a pluralityof centrifugally operable'grinding rolls, a spider carried bysaid quill shaft, a plow-supporting arm mounted upon said spider, means for clamping said plow-snp-porting arm upon said spider to permit rotative adjustment about the axis of said arm, a plurality of parallel arcuate ribs upon the face of the lowerportionof said arm concentric with respect to an axis substantially radial to the path of movement mentary to the ribs upon said plow-supporting arm and having a laterally offset end portion extending behind said plow-supporting arm, a bolt and slot connection between the upwardly extending member of said plow and said plow-supporting arm and a screw extending through the offset portion of the upwardly extending member of said plow abutting against the rear face

Description

Jan. 10, 1928. 1,655,499
w. A. GIBSON ADJUSTABLE PLOW FOR GENTRIFUGAL GRINDING MILLS Filed Dec. 29, 1924 2 Sheets-Sheet 1 Fig. 1.
a as
(Q 4 G Q 3 as Q6 2:! 2o .3 Q
as I4 a a \nvenTor. WilliumA.Gibson Jan. 10, 1928.
W. A. GIBSON ADJUSTABLE ILOW FOR CENTRIFUGAL GRINDING MILLS Filed Dec. 29. 1924 2 Sheef.s-Sheet 2 lnvenl'or. WiHi0mA.Gibson b /QQM Ml W Afiys.
Patented Jan. 10, 1928.
"UNITED v l' v 1,655,499 PATENT QOFFICE;
WILL AM as GIBSON, orVALLENrowN,rnNNsYLvANIA, ASSIGNOB ro BRADLEY rUL vnnrzna COMPANY, or ALLENTOWN, PENNSYLVANIA, A CORPORATION or MAINE.
ADJUSTABLE PLOW FOR CE NTRIFUGAL GRINDING MILLS.
Application filed December 29, 1924. serial No'..758,635 I This invention relates to improvementsin centrifugal grinding mills and the 'object thereof is to provide means for moreefiec tively delivering the material to be ground to the co-o'perating grinding members.
Centrifugal mills ofv this type comprise a grinding pan having an annular die therein, usually a plurality of centrifugally oper able grinding rolls co-operating with said annular die and a plowor plowsrotatable with said grinding roll or rolls and in ad- Vance thereof extending into the material to be ground andacting to deliver the material to; the co-operating grinding members.
In grinding mill constructions of this type heretofore constructed the plows have been secured in a predetermined rigid position. It has been found that the plow actsidiiferently upon different materials, such as those having different specific gravity, or upon materials differing in fineness, and particularly with a very different action upon coarse material and relatively fine material which is frequently introduced into the mill for repulverization.
The object of the present invention is broadly to provide means for adjustably supporting the plow-to enable it to be se cured in various different positions of adjustment.
One of the objects of the invention is to provide means for securing the plow atdifferent distances toward and from thembottom of the pan.
Another object of the invention vide means for differing the inclination or tilt of the plow so that the face whichserves to project the material toward the co-operating grinding members may be more or less inclined.
A further object of the invention is to provide means for rotatably adjusting the plow about the axis of itssupport so that the position of the ploW maybe varied with respect to the radius of the annular grinding die. j I
he present invention comprises means for accomplishing all of these purposes as well as easily operable means for securing the various adjustments. r I
l/Vhile the invention is applicable to numerous usual types of grindi1ig mills,,it illustrated herein asembodied ina centrifugal grinding mill of, the general type illustrated in Patent No. 1,175,436, Grrifiin,grant-- is to pro- I ed'iMarch 14, 1916, and No. 1,473,341, Gibson and Needham, granted November 6,
t e d awin -F a I i Fig. 1 ea view, partially in vertical section; of a centrifugal grinding mill of the type above described;
Fig. 2 's van enlarged detail front elevation of a plow-supporting arm and plow adjustably secured thereto embodyinga preferredform of theinvention, theplow-supporting arm being broken away;
Fig. 3 is a side elevation, of the same; and j j I Fig. is a view showing the plow-supporting arm in transversesect-ion and the plow andhthe means for securing the plow to said arm in elevation. V
The grinding mill illustrated in the-accompanying drawings comprises a base 1 having an upturned curb 2 forming a grinding pan to receive the material to be ground, agrinding ring or die 3 bein'g detachably secured between the upper portion of the curb '2 and a clan'iping section-4= which is secured to the curb 2, the upper portion of the curb and clamping member 4: being provided with inclined faces comple-f mentary itomperipheralinclined faces upon the grinding ringor die. The base 2 is also provided with extonsions or bossesfli I whichreceigve the lower ends of preferably A-shaped standards 6; upon the upper ends of which are mounted saddles 7 which support a transverse girder 8 whichsustains the rotatingpertsof the mill. I 1 The rotating members comprise afquill; shaft- 9 which is supported by a bevel gear 10 which rests upon the transverse girder 8 andis driven by a beveled pinion 11 upon a suitable driving shaft 12 j ournaled in bearings in the saddles 7 The quill shaft 9 is rotatably mounted upon astationary central shaft 13 the lower end of which is tapered andsuitably secured in a central boss 1 in; tegral with and extending upwardlyfrom the pan. The shaft 13 has secured to it a carrier 15 of general cylindrical form, the
outer wall of whichsurrounds a stationary annular dieB are rotatably mounted in the rocker heads. The base portion of the carrier is provided with downwardly and outwardly extending chutes 21 which deliver the material in proximity to the periphery of the pan and into the path of the crushing rolls.
The lower end of the quill shaft suports a horizontally disposed spider 22 which is made in sections to fit around and enclose the reduced lower end of the quill shaftwhich is provided with a rib 23 adapted to engage an annular recess in the spider and prevent the latter from longitudinal movement upon the quill shaft: This spider serves to support the plow or plows which travel in the grinding chamber beneath the'path of the rolls and force the material in the grinding pan into the path of the rolls.
The construction thus describe-d may be and desirably is similar to that disclosed in the prior patents above referred to.
In previous constructions the plows have been rigidly supported upon arms which in turn have been rigidly secured to the spider upon the lower end of the quill shaft. The object of the present invention, as heretofore mentioned, is to provide means for ad justably supporting the plow in such a manner that it may be secured in any or all of the various positions of adjustment so that the most effective action of the plow may be obtained for the particular kind of material which is being treated in the mill. The adjustments provided for by the present inven tion comprise, first, the bodily adjustment of the plow toward and from the bottom of the pan: second, a tilting adjustment by means of which the angular position of the face of the blade relative to its plane of movement may be varied; and, third, an adjustment about the axis of the plow support by means of which the angular relation of the blade to the radius of the annular die may be varied.
Any suitable means may be provided for accomplishing any or all of these adjustments within the spirit and scope of the claims.
'Tn the preferred embodiment of the invention illustrated herein the spider is provided with one or preferably a series of downwardly and outwardly extending sockets 24: which may be of cylindrical form and in which the upper ends 25 of cylindrical plow-supporting arms 26 are mounted and secured in any suitable manner as by set screws 27, or other suitable means which will permit the arm tobe rotat'ably adjusted about its aXis in such a manner that the plow. may be adjusted angularly with respect to the radius of the annular die.
The plows may be secured to the lower ends of the arms 26 in any suitable manner to provide for other adjustments. In the preferred construction illustrated the plow comprises a flat inclined blade 28 to engage the material and an integral upwardly extending preferably flat member or web 29 which is secured to the arm 26 by a bolt 30 and is provided at its upper end with a laterally extending arm 31 which extends behind and across the rear edge of the arm 26. A screw 32 seated in the arm 81 abuts against the rear edge of the arm and serves to retain the plow in adjusted position about the axis ofthebolt 30 as the engagement of the plow with, the material tends to rotate the plow about the axis of the bolt in aidirection which will force the end of the screw 32 against the rear edge of the arm Obviously by screwing up or unscrewing the screw 32 the plow may be tilted more or less relatively to the plane of its movement. By thus varying the angular position of the face of the plow the material may be projected upwardly at a greater or less angle.
It is desirable in treating dili'erent materials that the plow shall travel in paths at different distances from the bottom of the pan. This is accomplished by providing means by which the effective length of the plow-supporting arm may be varied. Means are provided in the present invention for producing this adjustment either separately or coincidentally with the tilting adjustment. This 'is accom 'ilished by providing the arm 26, or the member or web 29 of the plow, but preferably the arm 26 with a plurality of arcuate ribs 33 and the co-opcrating member, preferably the member 29 of the plow with a complementary arcuate rib 3d which is concentric with the axis of the bolt 30 which extends in a direction substantially radial to the path of movement of the plow. The stem of the bolt 30 e tends through and tits an aperture in the member 29 which is concentric with the rib 34, but is mounted in a slot extending longitudinally of the arm 26. A
By reason of this construction the plow may be adjusted longitudinally of the arm by unscrewing the not of the bolt and raising or lowering the position of the rib or in such a manner that it will inter-engage with selected ribs upon the arm 26 and thereupon setting up the bolt 30. By reason of the fact that the rib 34: is concentric with the axis of the boltand the ribs 33 are complementary in curvature to the rib 3-1 the tilting adjustment above described can be made at the same time by setting up or withdrawing the screw 32 the desired amount.
It will be apparent that by reason of the adjustments above described the plow can be raised or lowered relatively to the pan so that it will engage more or less of the material in the pan; the plow may be tilted to adjusted positions to cause the material'to be projected upwardly to a greater or less 7 height and the plow may be adjusted about I ment of parts may be made within the spirit and scope of the following claims.
Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is: i
, 1. In a centrifugal grinding mill comprising a pan, an annular die, a centrifugally operable grinding member therewith and a plow movable with said grinding member, means for supporting said plow including adjustable means for securing said plow in different vertically tilted positions relatively to the plane of said pan about an axis substantially radial to the path of 'i'novement of the Pl0\ 2. In a grinding mill comprising a pan,
an annular die, a plurality of co-operatingv grinding members rotatable about a common central axis co-operating with'said die, aplow-supporting arm rotatable about said central axis, a plow, interengaging members upon said plow and said arm and means pivotally connecting said plow to said arm.
operable to permit said plow to be secured in dilierent verticallytilted positions relatively to the plane of said pan.
In a grinding mill comprising a pan, an annular die, a plurality of co-operating grinding members rotatable about a common central axis co-operating with said die, a plow-supporting arm rotatable about said central axis, a plow, complementary faces upon said plow and arm having interengaging members and pivotal means for clamping said plow to said arm operable to per-' mit adjustment of said plow longitudinally of said arm and also rotatably about said pivotal connection. Y 1
l. In a grinding mill comprising a sta tionary' grinding member and a plurality of co-operat-ing grinding members rotatable about a common central axis, a plow-supporting member also rotatable about said central axis, a plow, complementary faces upon said plow and said arm, one of said co-operating plow-supporting arm. In testimony whereof, I have signed my name to this specification.
faces having a plurality of arcuate ribs and the other face having a complementary rib, a clamping bolt for securing said plow to said arm concentric with respect to said ribs and extending substantially radial to the path of movement of said plow and adjustable means for retaining said plow in a predetermined position of ad ustment about the axis of said .clamping bolt. I
5. In a grinding mill comprising a stationary grinding member and a plurality of co-operating grinding members] rotatable about a common central axis, a plow-supporting" member also rotatable about said central axis, a plow, complementary faces upon said plow and said arm, one of said faces having a plurality of arcuate ribs and the other face having a complementary rib, means for adjustably clamping said faces together including a bolt in one of said members concentric with its arcuate rib and extending substantially radial to the path of movement of he plow and seated in a slot 7 in the other member extending substantially in the direction of the axis of such member and adjustable means for retaining said -plow in a predetermined position of adjustment about the axis of said bolt.
6. Ina centrifugal grinding min comprising a grinding pan having a die, a central upright shaft, a quill shaft rotatable upon said upright shaft having a carrier supporting a pluralityof centrifugally operable'grinding rolls, a spider carried bysaid quill shaft, a plow-supporting arm mounted upon said spider, means for clamping said plow-snp-porting arm upon said spider to permit rotative adjustment about the axis of said arm, a plurality of parallel arcuate ribs upon the face of the lowerportionof said arm concentric with respect to an axis substantially radial to the path of movement mentary to the ribs upon said plow-supporting arm and having a laterally offset end portion extending behind said plow-supporting arm, a bolt and slot connection between the upwardly extending member of said plow and said plow-supporting arm and a screw extending through the offset portion of the upwardly extending member of said plow abutting against the rear face of said WILLIAM A. GIBSON.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11192117B2 (en) * 2016-11-15 2021-12-07 Neuman & Esser Process Technology Gmbh Mill

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11192117B2 (en) * 2016-11-15 2021-12-07 Neuman & Esser Process Technology Gmbh Mill

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