US1479173A - Grinding mill - Google Patents

Grinding mill Download PDF

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US1479173A
US1479173A US550017A US55001722A US1479173A US 1479173 A US1479173 A US 1479173A US 550017 A US550017 A US 550017A US 55001722 A US55001722 A US 55001722A US 1479173 A US1479173 A US 1479173A
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rollers
drum
ring
bearing
housing
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US550017A
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Cole David
Julius G Bergman
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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
    • B02C17/00Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/18Details
    • B02C17/181Bearings specially adapted for tumbling mills

Definitions

  • This invention relates -to grinding mills and particularly to supporting bearings for mills of the type requiring one end head to be readily removable, such for example as theso-called rod mills.
  • rod mills the grinding elements are heavy long as the internal length of These rods, wear ymore rapidly end ofthe mill and steel rods substantially as the drum.l
  • the rods must be inspected from so that badly worn rods may be and snarl. Otherthe mill sufremoving that the removal rotated while the head is removed, so that all the rods can be inspected without removal.
  • the loaded drum has imduty on the bearings,- and nion bearing, heavy weight of posed very. severe the mill on one trimbut the the structures heretofore used have developed diculties arising from excessive loads in journals, ings.
  • the present invention meets these conflicting requirements and offers a practical solution of past difficulties.
  • vpressure is equalized changed.
  • the design is purposely made such as to facilitate accuracy in manufacture, and permit the elimination of field adjustments.
  • rllhe entire bearing structure'for the ridinglring is however vtransversely adjustable as a whole to permit the bearing to be alined properly with the axis of the drum, and the truiinion bearing is formed with a spherical seat to permit the drum to move in response to such movements of the riding ring bearing structure.
  • the entire bearing structure for the riding ring is mounted so as to bc capable of rocking slightly in order to equalize the supporting roller pressure over the whole width of the riding ring.
  • the rugged nature of the supporting bearings for the riding ring and the provision for securing and maintaining alinement permit such location of the riding ring as will cause it to support more than half the load, preferably about two thirds of the load.
  • This permits the use of a short trunnion bearing and facilities feeding, the feed, as is usual in such mills, being passed through the trunnion.
  • the resulting structure has few small parts and is capable of economical accurate manufacture. parts of the riding ring bearing will maintain alinement. Only one field adjustment is possible and this secures alinement of the entire bearing structure. When this adjustment is correctly made the vdrum will have no endWise creep, so that correct adjustment is easily recognized. The adjustment one( ⁇ made is easily maintained.
  • Fig. 1 is a view, partly in elevation and vThe component partly in longitudinal section, showing the shell of a grindingdruig supported by one trunnion bearing and one riding ring.
  • Fig. 2 is a section on the line 2--2 of Fig. 1, on an enlarged scale.
  • Fig. 3 is a plan view of the supporting roller structure shown in Fig. 2.
  • Fig. 4 is an end elevation of the roller structure.
  • Fig. 5 is a section on the line 5 5 of Fig.
  • Fig. 6 illustrates a modified construction in which no trunnion bearing is used and in which the drum is supported on two riding rirgs and two supporting roller structures.
  • he grinding drum is made up of a plurality of ianged cylindrical sections 11, 12 and 13. It is closed at the feed end.l by a head 14 formed with a hollow trunnion 15 and a peripheral flange or web 16, and is closed Lat the discharge end by a head 17 having a central discharge opening 18.
  • the heads and cylindrical sections are connected together by bolts 19.
  • a driving ring gear 2O is bolted to the flange 16 on head 14, and a riding ring 21 having an inwardly extending web 22 surrounds the drum.
  • the web 22 extends between the flanges of sections 12 and 13 and is connected with such fianges by the bolts 19.
  • rlhe trunnion 15 is formed with a journal between the flanges 23, 24 and this turns in a bearinfg 25 which has a spherical external surface and is mounted in a spherical seat in the bearing box composed of the base casting 26 and cap 27.
  • rlFhe base casting 26 is mounted on any suitable fixed support.
  • the riding ring 21 is so placed as to take the majority of the load, an arrangement which permits reduction of the length of the bearing 25 surrounding trunnion 15, and thus facilitates feeding material to the drum.
  • the bearing structure which supports the riding ⁇ ring 21 is carried by a base casting 28 formed near its outer ends with two alined arcuate seats 29.
  • the centers of the arcs of seats 29 are in the plane of the axes of rollers 37 hereafter described.
  • a unitary housing 30, preferably formed as an integral casting is supported on the arcuate seats 29 of base 27 by means of arcuate pads 31, and two series of anti-friction rollers 33.
  • One series of rollers 33 is interposed between each. seat 29 and the corresponding pad 31.
  • the housing 30 is formed at its center with a well or depression which is defined at its corners by four parallel vertical guides 34.
  • Mounted in the guide 34 is a frame or yoke 35 generally! rectangular in form and provided with integral guides 36 at its cor@ ners.
  • Each guide 36 coacts with a corresponding guide 34, and the two sets of guides serve to constrain the frame 35 to right line movement up and down in housing 30.
  • rollers 37 Mounted near the ends of housingk30 are supporting rollers 37 upon which the riding ring 21 runs. Each roller 37 turns freely in a fixed shaft 38 clamped by means of caps 39 in seats near the ends of the housing 3U.
  • antifriction bearings may be used and for pur oses of illustration a cylindrical roll type o bearing is shown.
  • the inner race is shown at ,40, the outer race at 41, the interposed rollers at 42, and a combined retaining ring and dust guard at 43.
  • Vario-us commercial types of ball or roller bearings may be substituted.
  • the two rollers 37 and their bearings are so designed that they may, within a reasonable factor of safety, alone sustain the load imposed through 'the riding ring. To relieve them of part, and referably approximately half of the load, a ditional supporting rollers are provided.
  • rollers 44 which are freely rotatable on fixed shafts 45 which are clamped in sea-ts on the under side of frame 35 by means of the inverted caps 46.
  • the bearinof structure is preferably identical with that used for rollers 37.
  • Each cap 46 is provided with two downward projecting lugs 47 on which are seated the springs 48 whose lower ends bear on the bottom of the well or depression in housing 30. (See Fig. 2.) rll ⁇ he yoke or frame 35 4is thus supported by eight springs 48 and these springs are so -designed that the eight will support approximately half the total load. In other words the rollers 44 relieve the rollers 37 of approximately half the load the would otherwise be called upon to bear. crews 49 with suitable check nuts permit the housing 30 to be adjusted in the direction ofits length. rlhis is the only Held adjustment provided. c
  • Fig. 6 shows the use of two riding-rings and two riding-ring supporting bearin s to permit the elimination of the trunnion arl(fr cast base frame 50 takes the place of casting 27, and supports by means of rollers similar to the rollers 33 (not shown in Fig. 6) two housings 30y identical in all essential respects with the housing 30 of Figs. 1-5, and equipped with essentially the same adjusting screws 49, rolls 37, 44, guides 34, 36, frame 35, and supporting springs 48 as is the supporting bearing structure fully shown in Figs. 1 to 5, and already described. These parts, or such of them as are visible are indicated in Fig. 6 by the same reference numerals used to indicate them on Figs. l to 5. Details of construction are slightly Leraars varied in the structure of Fig. 6, but essentially it involves the use of -two riding rings and bearings of the type already described instead of one.v i
  • the shell of the grinding drum is indicated at 51 and may be made in sections. lt is provided with tworiding rings 52 which run on the rolls 37, 44 and have beveled flanges 53.
  • the flanges 53 run against beveled guide wheels 54, one for each ridin ring.
  • the wheels 54 are fast on vertical shafts 55 and the wheels and shaft turn in on step bearing 56 and an antifriction bearin 5 glhe bevels of the guide wheels and flanges are designed to give proper rolling contact and the wheels 54 prevent endwise creep of the drum.
  • the drum may be driven in any suitable manner and we show a ring gear 58.
  • rollers automatically divide the load among themselves, and yet are compelled by a very simple mechanical construction to maintain alinementwith each other. Furthermore the load is automatically equalized over the entire length ofthe supporting rollers.
  • the designv of all parts is such as to facilitate accurate manufacture, so that adjustments are unnecessary and are not rovided for.

Description

` D. COLE ET Al.
GRINDING MILL Filed April 6, 1922 3 Sheets-Sheet 2 W6' M M 1479 173 Jan' 1 1924 D. COLE ET Al. L
GRINDING MILL Patented dan. T, Tg2/al1.
NETE@ STATES airain 'Parana carica.
nam com am) JULIUS G. ameriten', or EL raso, TEXAS.
GBJINDING MILL.
Application med April 6, 1922. Serial No. 550,017,
To all whom it may concer/n:
Be it known that zen of the United BERGMAN, a subject residing at El Paso, i and State of Texas,
we, DAVID COLE, a citi- States, andA JULiUs G.
of the King of Sweden,
n the county of El Paso have invented certain tion.
This invention relates -to grinding mills and particularly to supporting bearings for mills of the type requiring one end head to be readily removable, such for example as theso-called rod mills. In a rod grinding mill the grinding elements are heavy long as the internal length of These rods, wear ymore rapidly end ofthe mill and steel rods substantially as the drum.l
at the feed hence musgbe periodically turned end for end to`ualize the wear. time to time,
removed before they bend wise the grinding eiciencyof fers, and the work of consumes much of the head be a drum be so supported that it can be valuable time.
The rods must be inspected from so that badly worn rods may be and snarl. Otherthe mill sufremoving that the removal rotated while the head is removed, so that all the rods can be inspected without removal. These requirements have heretofore been met by supporting and one riding ring,
the loaded drum has imduty on the bearings,- and nion bearing, heavy weight of posed very. severe the mill on one trimbut the the structures heretofore used have developed diculties arising from excessive loads in journals, ings.
require the distributi and mis-alinement of the bear- The heavy loads met in this service on of the load over several supporting rollers, and unless close y alinement and reasonably close equalization of load on the various rollers and 'their bearings are maintained,
destructive wear occurs before the faulty conditions are detected.
A simple rugged from the cost and construction is essential,
operation standpoint.
The present invention meets these conflicting requirements and offers a practical solution of past difficulties.
No attempt at per feet equalization of the the bent rods.
vpressure is equalized changed. The design is purposely made such as to facilitate accuracy in manufacture, and permit the elimination of field adjustments.
rllhe entire bearing structure'for the ridinglring is however vtransversely adjustable as a whole to permit the bearing to be alined properly with the axis of the drum, and the truiinion bearing is formed with a spherical seat to permit the drum to move in response to such movements of the riding ring bearing structure.
Furthermore the entire bearing structure for the riding ring is mounted so as to bc capable of rocking slightly in order to equalize the supporting roller pressure over the whole width of the riding ring. When the the parts are in stable equilibrium.
The rugged nature of the supporting bearings for the riding ring and the provision for securing and maintaining alinement permit such location of the riding ring as will cause it to support more than half the load, preferably about two thirds of the load. This permits the use of a short trunnion bearing and facilities feeding, the feed, as is usual in such mills, being passed through the trunnion. The resulting structure has few small parts and is capable of economical accurate manufacture. parts of the riding ring bearing will maintain alinement. Only one field adjustment is possible and this secures alinement of the entire bearing structure. When this adjustment is correctly made the vdrum will have no endWise creep, so that correct adjustment is easily recognized. The adjustment one(` made is easily maintained.
Preferred embodiments of the invention are shown-in the accompanying drawings, in whichz` Fig. 1 is a view, partly in elevation and vThe component partly in longitudinal section, showing the shell of a grindingdruig supported by one trunnion bearing and one riding ring.
Fig. 2 is a section on the line 2--2 of Fig. 1, on an enlarged scale.
Fig. 3 is a plan view of the supporting roller structure shown in Fig. 2.
Fig. 4 is an end elevation of the roller structure.
Fig. 5 is a section on the line 5 5 of Fig.
Fig. 6 illustrates a modified construction in which no trunnion bearing is used and in which the drum is supported on two riding rirgs and two supporting roller structures.
he grinding drum is made up of a plurality of ianged cylindrical sections 11, 12 and 13. It is closed at the feed end.l by a head 14 formed with a hollow trunnion 15 and a peripheral flange or web 16, and is closed Lat the discharge end by a head 17 having a central discharge opening 18. The heads and cylindrical sections are connected together by bolts 19.
A driving ring gear 2O is bolted to the flange 16 on head 14, and a riding ring 21 having an inwardly extending web 22 surrounds the drum. The web 22 extends between the flanges of sections 12 and 13 and is connected with such fianges by the bolts 19.
rlhe trunnion 15 is formed with a journal between the flanges 23, 24 and this turns in a bearinfg 25 which has a spherical external surface and is mounted in a spherical seat in the bearing box composed of the base casting 26 and cap 27. rlFhe base casting 26 is mounted on any suitable fixed support.
It will be observed that the riding ring 21 is so placed as to take the majority of the load, an arrangement which permits reduction of the length of the bearing 25 surrounding trunnion 15, and thus facilitates feeding material to the drum.
The bearing structure which supports the riding` ring 21 is carried by a base casting 28 formed near its outer ends with two alined arcuate seats 29. The centers of the arcs of seats 29 are in the plane of the axes of rollers 37 hereafter described.
A unitary housing 30, preferably formed as an integral casting is supported on the arcuate seats 29 of base 27 by means of arcuate pads 31, and two series of anti-friction rollers 33. One series of rollers 33 is interposed between each. seat 29 and the corresponding pad 31. This construction permits a rocking movement of the housing 30 on an axis at right angles to the axis of the drum, and insures uniform bearing pressure throughout the length of the supporting rollers.
The housing 30 is formed at its center with a well or depression which is defined at its corners by four parallel vertical guides 34. Mounted in the guide 34 is a frame or yoke 35 generally! rectangular in form and provided with integral guides 36 at its cor@ ners. Each guide 36 coacts with a corresponding guide 34, and the two sets of guides serve to constrain the frame 35 to right line movement up and down in housing 30.
Mounted near the ends of housingk30 are supporting rollers 37 upon which the riding ring 21 runs. Each roller 37 turns freely in a fixed shaft 38 clamped by means of caps 39 in seats near the ends of the housing 3U. As shown in Fig. 5 antifriction bearings may be used and for pur oses of illustration a cylindrical roll type o bearing is shown. The inner race is shown at ,40, the outer race at 41, the interposed rollers at 42, and a combined retaining ring and dust guard at 43. Vario-us commercial types of ball or roller bearings may be substituted.
The two rollers 37 and their bearings are so designed that they may, within a reasonable factor of safety, alone sustain the load imposed through 'the riding ring. To relieve them of part, and referably approximately half of the load, a ditional supporting rollers are provided.
These are the rollers 44 which are freely rotatable on fixed shafts 45 which are clamped in sea-ts on the under side of frame 35 by means of the inverted caps 46. The bearinof structure is preferably identical with that used for rollers 37.
Each cap 46 is provided with two downward projecting lugs 47 on which are seated the springs 48 whose lower ends bear on the bottom of the well or depression in housing 30. (See Fig. 2.) rll`he yoke or frame 35 4is thus supported by eight springs 48 and these springs are so -designed that the eight will support approximately half the total load. In other words the rollers 44 relieve the rollers 37 of approximately half the load the would otherwise be called upon to bear. crews 49 with suitable check nuts permit the housing 30 to be adjusted in the direction ofits length. rlhis is the only Held adjustment provided. c
Fig. 6 shows the use of two riding-rings and two riding-ring supporting bearin s to permit the elimination of the trunnion arl(fr cast base frame 50 takes the place of casting 27, and supports by means of rollers similar to the rollers 33 (not shown in Fig. 6) two housings 30y identical in all essential respects with the housing 30 of Figs. 1-5, and equipped with essentially the same adjusting screws 49, rolls 37, 44, guides 34, 36, frame 35, and supporting springs 48 as is the supporting bearing structure fully shown in Figs. 1 to 5, and already described. These parts, or such of them as are visible are indicated in Fig. 6 by the same reference numerals used to indicate them on Figs. l to 5. Details of construction are slightly Leraars varied in the structure of Fig. 6, but essentially it involves the use of -two riding rings and bearings of the type already described instead of one.v i
The shell of the grinding drum is indicated at 51 and may be made in sections. lt is provided with tworiding rings 52 which run on the rolls 37, 44 and have beveled flanges 53. The flanges 53 run against beveled guide wheels 54, one for each ridin ring. The wheels 54 are fast on vertical shafts 55 and the wheels and shaft turn in on step bearing 56 and an antifriction bearin 5 glhe bevels of the guide wheels and flanges are designed to give proper rolling contact and the wheels 54 prevent endwise creep of the drum. Of course, when the housings 30 are properly mounted parallel to each other, and so adjustedtransversely to the axis of the drum by means of screws 49 as to bring the axis\of the drum and the axis of the rollers parallel, there is no tendency to creep, and the duty on bevel wheels 54 is light. This, ofcourse, is the normal condition. f
The drum may be driven in any suitable manner and we show a ring gear 58.
It will be observed that in both embodiments of the invention herein illustrated the rollers automatically divide the load among themselves, and yet are compelled by a very simple mechanical construction to maintain alinementwith each other. Furthermore the load is automatically equalized over the entire length ofthe supporting rollers. The designv of all parts is such as to facilitate accurate manufacture, so that adjustments are unnecessary and are not rovided for.
The invention is suscepti le of various slightlydifferent embodiments, and various modifications, all falling within the scope of the appended claims, are contemplated.
In both embodiments of the invention alinement of the axes of the supporting rollers with the axis of the drum is secured by transverse relative adjustment of two bearings. Relative adjustability of two bearings is the essential thing and one bearing might bel adjustable as in Figs. 1 to. 5 or both as in Fig. (i without departing :from the spirit of' the invention. Where only one is adjustable it may obviously be either one.
lli/'hat is claimed is 1. The combination of a drum provided with a riding ring; a housing provided with a pair ot' parallel rollers serving to support said ring; a frame movably mounted in said housing and positively guided thereby to move in a right line toward and from said riding ring; a roller rotatably mounted in said frame on an axis parallel to the axes of the first named rollers; and a spring structure urging said frame toward said riding ring.
2. The combination of a drum provided with a riding ring; a bearing structure including a frame and a plurality of rollers supported thereby and in rolling contact with said ring; and supporting means for said bearing structure serving to permit said structure to rock about an axis substantially atv right angles to the axis of said drum.
3. The combination of a drum provided with a riding ring and a trunnion; a self alining bearing for said trunnion; a supporting bearing structure comprising a frame and a plurality of parallel rollers supported thereby and in rolling contact with said ring; and means for adjusting the position of said bearing structure relatively to said trunnion bearing in a direction transverse to the axis of said drum to establish parallelism between said rollers and the axis of said drum. p
4. The combination of a drum provided with a riding ring; a housing provided with a. pair of parallel rollers serving to support said ring; a support for said housing serving to permit the housing to rock' about an axis at right angles to the axis of the drum whereby the pressure between said rollers and ring is equalized over the length of the rollers; a frame movably mounted in said housing and positively guided thereby to move in a right line toward and from said riding ring; a roller rotatably mounted in said frame on an axis parallel to the axes ot' the first named rollers; and a spring structure urging said frame toward said riding ring.-
5. The combination of a drum provided with a riding ring and a trunnion; a self alining bearing for said trunnion; a housing provided with a pair of parallel rollers serving to support said ring; a frame movably mounted in said housing and positively guided thereby to move toward and from said riding ring; a roller rotatably mounted in said frame on an axis parallel to the axes of the first named rollers; a spring structure urging said frame toward said riding ring; and means for shifting the position of said housing relatively to said trunnion bearing in a direction transverse to the axis of said drum to-establish parallelism between the axesofl said rollers and the axis of said drum.. j
' 6.' .The combination of a drum provided with a riding ring and a trunnion; a self alining bearing for said trunnion; a housing `provided'vvith a pair of parallel rollers-servingto support said ring; a support for said housing serviny 'to permitthe housing to rock about an axis at right angles to the axis of the drum whereby the pressure between said rollers and ring is equalized over the length of the rollers; a frame movably mounted in said housing and positively guided thereby to move toward and from said riding ring; a roller rotatably mounted drum to establish parallelism between the in said frame on an axis parallel to the axes axes of said rollers and the axis of saiddrum.. of the first named rollers; a spring structure lln testimony whereof We have signed our 'l0 urging said frame toward said riding ring; names to this specification.
5 and means for shifting the position of said housing relatively to said trunnion bearing DAVID COLE. in a direction transverse to the axis of said JULllUS G. BERGMAN.
US550017A 1922-04-06 1922-04-06 Grinding mill Expired - Lifetime US1479173A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2430487A (en) * 1945-06-06 1947-11-11 Harold B Wessenger Compensating roller support
US2444432A (en) * 1945-01-15 1948-07-06 William F Eckert Two-way roller guide
US2570082A (en) * 1948-09-23 1951-10-02 Jr Samuel W Traylor Support for rotary kilns
US3023056A (en) * 1959-05-04 1962-02-27 Machinery Company Const Concrete mixing drum and method of making same
DE3306745A1 (en) * 1983-02-25 1984-08-30 Krupp Polysius Ag, 4720 Beckum Bearing for rotary drums

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2444432A (en) * 1945-01-15 1948-07-06 William F Eckert Two-way roller guide
US2430487A (en) * 1945-06-06 1947-11-11 Harold B Wessenger Compensating roller support
US2570082A (en) * 1948-09-23 1951-10-02 Jr Samuel W Traylor Support for rotary kilns
US3023056A (en) * 1959-05-04 1962-02-27 Machinery Company Const Concrete mixing drum and method of making same
DE3306745A1 (en) * 1983-02-25 1984-08-30 Krupp Polysius Ag, 4720 Beckum Bearing for rotary drums

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