US3339853A - Grinding mill - Google Patents

Description

p 1967 M. s. SQHAN SKI 3,339,853

GRINDING MILL Filed April 9, 1965 3Sheets5heet 1 Q I INVENTOR My/eo/v J. ff/JCHANSK/ BY 45mm 63M ATTORIE'EYS p 1967 M. s. MISCHANSKI GRINDING MILL 3 Sheetssheet 2 Filed April 9, 1965 INVENTOR l7/5CHA/VJK/ @MAW - Sept. 5, 1967 VI GRINDING MILL Filed April 9, 1965 .lll! 25 r 82 i a? I 0 78 o T Li 1 I I I 7| 32 80 5: 1 62 M. s. MISCHANSK! 3,339,853

5 Sheets-Sheet 3 United States Patent 3,339,853 GRINDING MILL Myron Steven Mischanski, 27 Englewood Road,

. Clifton, NJ. 07012 Filed Apr. 9, 1965, Ser. No. 449,678 9 Claims. (Cl. 241-110) ABSTRACT OF THE DISCLOSURE A grinding mill having an upright casing with a cylindrical grinding ring therein. A plurality of arcuately spaced grinding rollers are supported on arms hingedly connected to a block mounted on a rotatable main shaft. Fluid cylinder and piston combinations are adapted to impart outward thrust against the rollers.

This is a continuation-in-part application of my application Ser. No. 338,119 filed Jan. 16, 1964, now abandoned.

This invention relates to grinding mills for comminuting solid material and, in particular, to mills of this character which employ fluid pressure responsive components for controlling the pressure of grinding rollers against the inner face of a grinding ring.

It is known that .the size and dimensions of the rollers in grinding mills utilizing centrifugal and fluid pressure forces are important factors in determining their operative efiiciency both in terms of production rate and power requirements. In general, it may be said that the heavier the rollers, the greater the. grinding pressure due to centrifugal force for a given rate of roller rotation on the grinding ring, thus permitting diminished rotation rates for attaining the desired production rates, and the larger the rollers, the larger the particles of material that maybe accommodated in the nip defined by the roller surface and the grinding ring. It has been found that in a mill using forced air to remove the pulverized material output actually increases at the reduced rates of rotation permitted by the larger rollers because there is less air turbulence in the grinding regions of the mill.

In machinery design, space requirements will frequently dictate the size of components. It was discovered that by suspending the rollers from pivotal elements which are located above the region bounded by the grinding ring and the block on which the elements are mounted additional space is afforded in this region to accommodate the larger size rollers. The pivotal movement of the principal operating elements dispenses with those mechanical problems inherent in sliding parts which have a support function, such problems resulting from the heat of friction, special lubrication requirements, cocking of elements out of their intended line of action, sealing, etc.

In one form of the invention there is provided a plurality of cylinder and piston combinations supported by the block, each piston being adapted to impart outward thrustto one of the rollers to urge it against the grinding face, and means areprovided. for admitting fluid under pressure into the cylinder for imparting such thrust.

In another form of the invention, opposed grinding rollers are interconnected by a single cylinder and piston combination so that movement of the piston exerts an outwardly directed thrust against each of its corresponding rollers.

4 In still another form of the invention, adjacent grinding rollers are interconnected by a single cylinder and piston combination so that movement of the piston simultaneously exerts an outwardly directed force against each .of the rollers. Each of the rollers is provided with angular brackets for mounting the cylinder and piston combination, the angle being dependent upon the number of 3,339,853 Patented Sept. 5, 1967 rollers employed. For example, if a total of 4 rollers are A feature of the invention resides in the provision of a new and improved grinding mill which requires considerably less space for mounting the rollers. That is, substantially less space is required between diametrically opposite rollers than heretofore thought necessary.

Another feature of the invention resides in the elimination of elements heretofore considered necessary for actuating the rollers in an outwardly direction. It is intended by the invention to eliminate the number of fluid pistons and cylinders and their mounting means required to exert thrust against the rollers.

Still further, another feature of the invention is the provision of a new and improved grinding mill which relieves stresses acting upon the central shaft, thereby providing a machine having a longer life with less maintenance costs. Further, according to the present invention covering means may readily be positioned over the piston rod assembly in order to maintain a substantially dustfree'environment.

v A further feature of the invention resides in the provision of a new and improved grinding mill which is designed to enhance operating efiiciency, whichis reliable, compact, durably constructed, practical and economical.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception on which this disclosure is based may readily be utilized as the basis for the designing of other structures for carrying out the several purposessof the invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of the invention. Several embodiments of the invention have been chosen for purposes of illustration and description, and are shown in the accompanying drawings, forming a part of the specification, wherein:

FGURE l is a section showing the improved grinding mill whichis taken on line 1-1 of FIGURE 2,

FIGURE 2 is a section taken on line 2-2 of FIG- URE 1;

FIGURE 3 is a partial vertical section taken on line 3-3 of FIGURE 2 on an enlarged scale;

FIGURE 4 is a sectional view similar to FIGURE 2, but showing another embodiment of the invention; and

FIGURE 5 is a sectional view similar to FIG. 2 but showing still another embodiment of the invention.

In the embodiment of the invention illustrated in FIG- URES 1 to 3, the grinding mill includes a block 2, serving to support the principal components of the mill, which is keyed to the main shaft 4. A bevel gear 6 is 'splined to the shaft 4 and is in turn driven by a pinion 8 mounted on the end of pinion shaft 10. Secured to the other end of the vmain shaft 4 is a housing 12 having an internal air chamber 14 which communicates with an air supply (not shown) through conduit 16 which turns with the main shaft. The conduit 16 is provided with a swivel coupling (not shown) intermediate its length, the upper portion of the conduit 16 above the coupling being stationary.

Secured to the block 2 and overhanging each of its four sides is a cylinder supporting plate 18. On each plate is disposed a cylinder 20 having an internal piston 21. To each of the four corners of the block 2 is integrally secured an ear 22 within which is disposed a stationary shaft 24. Journalled on each of the shafts 24 is housing 25 of roller supporting arm 26 supported in bearings above boss 27 atop ear 22, the arm being intermediately bent to accommodate the piston bearing on its free end. In another embodiment of the invention, as best seen in FIGURE 4, supporting arms 26 are provided with brackets 78 and 80, as shown. A single cylinder 82, piston 84 and piston rod 86 interconnects brackets 78 and 80, respectively, cylinders 82 being fixedly mounted on brackets 78 and piston rods 86 being pivotally mounted on brackets 80 by means of clevis 88. It will be appreciated that one cylinder, piston and piston rod is positioned slightly above the other cylinder, piston and piston rod in order for them to cross over without interfering with each other. This embodiment has several advantages, for example, less space i required for one than is required for two cylinder and piston combinations so that the space required between opposing rollers is thereby reduced. This is particularly important in small size grinding apparatus. Further, economical savings are encountered with this embodiment due to the elimination of onehalf of the number of pistons, cylinders, piston rods and mounting means therefor. Moreover, according to this embodiment of the invention there is less stress on the central shaft 4 due to the balancing effect between opposed rollers. For purposes of preventing dirt, dust or foreign matter from coming into contact with the piston push rods 86, a stocking 90 may readily be fitted thereover as shown by the dashed line in FIG. 4.

In still another form of the invention, as seen in FIG. 5, roller supporting arms 26 are provided with inwardly projecting brackets 92 and 94. Adjacent brackets 92 and 94 are interconnected by a single cylinder 96, piston 98 and piston rod 100, cylinder 98 being fixedly attached to bracket 92 and piston rod 100 being pivotally attached to bracket 94. This embodiment also has certain advantages including the elimination of elements heretofore deemed necessary.

As best seen in FIGURE 3, a hose 27a is slipped over the boss 27 with the upper end thereof disposed over a hub depending from housing 25 of the arm 26 and is provided with hose clamps to seal off the bearings which are similar to those provided for in the four grinding rollers 22 described below. A cover plate 29 bolted to the housing 25 seals the latter against the entrance of dust. Integrally extending from the free end of each arm is a vertical hub 28 within which is housed stationary shaft 30. The hubs 28 are supported by their respective arms substantially above the top surface of block 2 virtually extended.

Grinding rollers 32 are supported in bearings on the respective shafts 30 and are adapted to engage grinding ring 34 carried on the inner surface of the casing 36 of the mill. The grinding rollers are supported for rotation on upper and lower bearing rollers 38 and 40, respectively, disposed between inner races 42 and 44 respectively, and outer races 46 and 48, respectively. A spacer 50 supports the outer races and spacer 52 supports the inner races. Spanner nut 54 and nut 56 and lock washer 57 on threaded extension 58 of the shaft 30 maintains the hearing assemblies in proper relation to the shaft and the grinding rollers. The interior of the rollers is kept dust free by means of bottom cap 60 and top seal 62 which is filled with packing material about the shaft 30.

Each of the cylinders 20 is in communication by means of conduit 64 with the air chamber of the housing 12. Similarly, cylinders 82 (FIG. 4) and 96 (FIG. are in communication with an air supply source. The accumulative forces acting on the rollers arising from centrifugal force, which is a function of roller mass and velocity, and air pressure can be precisely controlled depending on the material being ground and the degree of pulverization desired by regulating the pressure of the air supply. The total absence of roller supporting structure in the space between the rollers and the block 2 permits of larger size rollers than have been used heretofore which reduces the velocity of roller rotation required to attain a given centrifugal force. Obviously fluids other than air may be used in the cylinders.

The material to be ground is fed into a hopper 67 affixed to the mill at one side thereof and is forced into the mill by a rotary mounted impeller 68 driven by any desired means (not shown). A deflector plate 69 is bolted or otherwise aflixed to the upper portion of the casing for deflecting the material downwardly between the grinding ring and rollers.

The comminuted material is drawn ofl upwardly through the casing by means of a cyclone collector connected by piping (not shown) with the top of the upper portion thereof. Air for the upward flow of the comminuted material is drawn into the mill by the cyclone collector through a series of radially arranged openings 70 in the lower portion of the casing and which openings are provided with grills 71 or other means for regulating the quantity of air admitted through the openings. The coarse material falls onto a platform 72. A series of arms 75 having plow shaped free ends 76 are bolted or otherwise aflixed to the block 2 and rotates therewith for throwing the coarse material upwardly between the grinding rollers 32 for additional grinding action.

From the foregoing it will be seen that I have conceived a novel and highly desirable grinding mill for comminuting solid material.

Although several embodiments of the invention are herein disclosed for purposes of explanation, further modifications thereof, after study of this specification, will be apparent to those skilled in the art to which the invention pertains. Reference accordingly should be had to the appended claims in determining the scope of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being supported by arms secured to one end of said rollers, said arms being hingedly connected to the block, a plurality of cylinder and piston combinations, each of said pistons being adapted to impart outward thrust against said rollers, means for admitting fluid under pressure in said cylinders for imparting said thrust, and means for driving said shaft in rotation.

2. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being supported by arms secured to one end of said rollers, said armsv being hingedly connected to the block, a plurality of cylinder and piston combinations, opposed rollers being interconnected by a single cylinder and piston combination, means for admitting fluid under pressure into said cylinders for imparting outwardly directed thrust against said opposed rollers respectively, and means for driving said shaft in rotation.

3. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being supported by arms secured to one end of said rollers, said arms being hingedly connected to the block, a plurality of cylinder and piston combinations, adjacent rollers being interconnected by a single cylinder and piston combination, means for admitting fluid under pressure into said cylinders for imparting outwardly directed thrust against said adjacent rollers respectively, and means for driving said shaft in rotation.

4. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being supported by arms secured to one end of said rollers, said arms being hingedly connected to the block, a plurality of cylinder and piston combinations supported by said block, each of said pistons being adapted to impart outward bias on one of said rollers against said grinding ring, means for admitting fluid under pressure in said cylinders for imparting said thrust, and means for driving said shaft in rotation, the hinged connection of each of the arms being above the top surface of the block whereby said rollers may be suspended in the annular space defined by the ring and the block free of roller supporting structure between said rollers and said block.

5. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being rotatably supported on upwardly extending axes by arms secured to one end of said rollers, said arms being hingedly connected to the block, a plurality of cylinder and piston combinations, said pistons being adapted to impart outward bias on said rollers, means for admitting fluid under pressure in said cylinders, for imparting said bias, and means for driving said shaft in rotation, the hinged connection of each of the arms being above the top surface of the block whereby said rollers may be suspended in the annular space defined by the ring and the block free of roller supporting structure between said rollers and said block.

6. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage aid inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being rotatably supported on vertically confined axes by arms secured to one end of said rollers, said arms being hingedly connected to the block in offset relation from the axes of the rollers respectively, a plurality of cylinder and piston combinations supported by said block, each of said pistons being adapted to impart outward bias on one of said rollers against said grinding face, means for admitting fluid under pressure in said cylinders for imparting said bias, and means for driving said shaft in rotation, the hinged connection of each of the arms being above the top surface of the block whereby said rollers may be suspended in the annular space defined by the ring and the block free of roller supporting structure between said rollers and said block.

7. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being rotatably supported on upwardly extending axes by arms secured to one end of said rollers, said arms being bent and hingedly connected to the block in offset relation from the axes of the rollers respectively, a plurality of cylinder and piston combinations, each of said pistons being adapted to impart outward bias on said rollers against said grinding face respectively, means for "admitting fluid under pressure in said cylinders for imparting said outward bias to said pistons respectively, and means for driving said shaft in rotation, the hinged connection of each of the arms being above the top surface of the block whereby said rollers may be suspended in the annular space defined by the ring and the block free of roller supporting structure between said rollers and said block.

8. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being rotatably supported on upwardly extending axes by arms secured to one end of said rollers, said arms being bent and hingedly connected to the block in off-set relation with the axes of the rollers respectively, a plurality of cylinder piston combinations, the arms rotatably supporting opposed rollers being interconnected by a single cylinder, piston and piston rod combination, said cylinder being mounted on one of said arms and said piston rod being pivotally connected to the other of said arms respectively, means for admitting fluid under pressure into said cylinder for imparting outwardly directed thrust against said opposed rollers respectively, and means for driving said shaft in rotation, the hinged connection of each of the arms being above the top surface of the block whereby said rollers may be suspended in the annular space defined by the ring and the block free of roller supporting structure between said rollers and said block.

9. In a mill for comminuting solid material, a casing supported in upright relation, a cylindrical grinding ring supported by said casing and having a peripheral inner grinding face, a plurality of arcuately spaced grinding rollers adapted to engage said inner grinding face, a rotatable main shaft, a block mounted on said shaft, said rollers being rotatably supported on upwardly extending axes by arms secured to one end of said rollers, said arms being bent and hingedly connected to the block in off-set relation from the axes of the rollers respectively, each of said arms supporting inwardly projecting brackets, adjacent brackets being pivotally interconnected by a single cylinder piston and piston push rod respectively, means for admitting fluid under pressure into said cylinder for imparting outwardly directed thrust against said adjacent rollers respectively, and means for driving said shaft in rotation, the hinged connection of each of the arms being above the top surface of the block whereby said rollers may be suspended in the annular space defined by the ring and the block free of roller supporting structure between said rollers and said block.

References Cited UNITED STATES PATENTS 8/1920 Stout 241-131 3/ 1962 Mischanski 24l131

Claims (1)

1. IN A MILL FOR COMMINUTING SOLID MATERIAL, A CASING SUPPORTED IN UPRIGHT RELATION, A CYLINDRICAL GRINDING RING SUPPORTED BY SAID CASING AND HAVING A PERIPHERAL INNER GRINDING FACE, A PLURALITY OF ARCUATELY SPACED GRINDING ROLLERS ADAPTED TO ENGAGE SAID INNER GRINDING FACE, A ROTATABLE MAIN SHAFT, A BLOCK MOUNTED ON SAID SHAFT, SAID ROLLERS BEING SUPPORTED BY ARMS SECURED TO ONE END OF SAID ROLLERS, SAID ARMS BEING HINGEDLY CONNECTED TO THE BLOCK, A PLURALITY OF CYLINDER AND PISTON COMBINATIONS, EACH OF SAID PISTONS BEING ADAPTED TO IMPART OUTWARD THRUST AGAINST SAID ROLLERS, MEANS FOR ADMITTING FLUID UNDER PRESSURE IN SAID CYLINDERS FOR IMPARTING SAID THRUST, AND MEANS FOR DRIVING SAID SHAFT IN ROTATION.

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