US2610802A - Variable unit pressure muller - Google Patents

Description

SePt- 15, 1952 R. L. MolLvAlNE 2,610,802

2 sm'rs-SHEET 1 fz: Veni 471-' E019 eri/L. Nall va/ze EH fi/4. yal/M5 sept. 16, 1952 R. 1 MlLvAlNE 2,610,802

VARI-ABLE UNIT PRESSURE MULLER Filed Sept. 14, 1948 2 SHEETS-SHEET 2 z/EUUJ" Robert' L. Nall zfqzze Patented Sept. 16,` '1952 VARIABLE UNIT PRE-SSR MJL Robert L. Mcllvaine, Glencoe, Ill., assigner, by

mesne assignments, to HerbertSimpson Corporation, Chicago, Ill., a corporation of Illinois Application September 14, 1948,*Serial No. 49,229

' y 1 claim. (o1. 241+1s2) This invention relates to improvements in mulling machines.

More particularly it has to do with a novel type of mulling machine wherein the pressure exerted by the muller wheels on the material being worked in the crib thereof is controlled by mechanical means acting through the muller wheels.

In the mulling of materials such as sand or sand mixtures high unit pressures are desirable to efliciently mix and work the material. These pressures are usually achieved by varying the weight of the muller wheels. -However, some materials, particularly light bodies such as air floated clays, do not set up enough frictional resistance to the mulling operation to causethe muller wheels to rotate. Thus, it is desirable when working such materialsto use light mullers with low inertia values and attain high unit muller pressures through mechanicalmeans acting through the muller wheels. y

It is, therefore, an important object of the kpres-- ent invention to providev a mulling machine wherein themuller wheels `have a low inertia value and wherein high unit mulling Vpressures are attained through use of a mechanical means other than' the muller wheels themselves.

A further object of the present invention is to provide a muller in which fluid actuated power cylinders are used in conjunction with the muller wheels to control the amount of unit pressure applied against the material being processed.

Another object of this invention is the provision of means for varying the unit pressure exerted on the material being mulled while the machine is in operation. n y

According to the teachings of thel present invention there is provided a set of muller wheels of relatively light weight pivotally mounted from the crosshead or turret of a mulling machinejfor rolling movement in a circular path on thefbed-` plate of the machine. The turret is rotated by a power driven center vertical shaft. A doubleacting Huid-actuated power cylinder is rigidly mounted on an upper tubularfextension of the turret so that its downwardly extending'piston rod bears against an arm member which extends substantially axially from the muller wheel. A fluid, such as air or oil, is brought byfmeans of a center tube and a revolving fluid type joint to a distribution control boxmounted on the upper tubular extension of the turret. The valves in the control box may be suitable operated by an electrically operated control valve located adjacent' the control box and supplied with elec.-

trical energy by means of a commutatcr mounted on the upper end of the tubular extension.

` When iluid is applied to the top of the power cylinder, pressure is exerted directly downwardly against said axially extending arm causing the muller wheel to be pressed downwardly against the material in the crib 'with any unit pressure up to the'pressure capacity ofthe fluid cylinder. When fluid is applied tothe lower e'nd of the power cylinder a reverse pressure is applied to the axial extending arm which tends to liftthe muller away from the bedplate of 'the machine and it may be so regulated as to move the muller wheel completely out of the material being worked.y

Other and further features, advantages and objects of the' present invention will be readily apparent to those skilled in the art from the following ydetailed description of the annexed sheets of drawings` f On the drawings: y

Figure 1 is a top planv view of the mulling machine constructed according to the teachings of the present invention.

'Figure 2 is a vertical sectional view taken substantially on line II-II in Figure l.

As shown on the drawings:

In Figures 1 and 2, the reference numeral I0 indicates generally a mulling machine including a crib having a flat base plate II of circular configuration having an upstanding flange I2 extending around the periphery of the plate. ,y A

` cap screws I5. This secondary plate is made of a special wear resistant material as also is a wear plate I8 disposed on the base plate I I,

A tubular bearing support housing. I9 is secured by cap screws 20 in an opening 2I in the base plate II and in the wear plate I8.

'Rotation of the mulling apparatus is carried out by a drive shaft 23, which is journaled'in roller bearings '24 at the lower end of the support housing I9 and is driven by an electric motor 25 through a gear drive 26. At its upper end, the drive shaft is keyed to a turret 21 which is supported on the housing I9. Thus, as the shaft 23 is rotated the tur-ret 21 is also rotated. An arm 28, Figure l, extends outwardly from a sleeve portion 29 formed integral with the turret 21 to support a scraper holder- 30 at the lowerend of which a scraper and plow member 3| is secured by cap screws 32.

The scraper is arranged to scrape material from the side and bottom walls of the crib and direct it inwardly toward the center of the crib. As the material moves inWa-rdly it is toppled over the inner end of the scraper blade, the height of which decreases progressively toward its inner end.

As seen in Figure 1, a sleeve portion 33 on the turret 21 has an arm 34 projecting outwardly therefrom to support, through bolts 35, a curved plow blade 3G. This plow blade is arranged at its innermost end 36a to scrape material from the support member I9 and is curved to urge the material outwardly as the turret rotates in the crib. The blade of the plow is of a height at its outermost portion 36h to permit material to topple thereover as the turret rotates, providing ,a zone in which material is in a loose tumbled condition.

Oppositely disposed in the crib of the machine and arranged to rotate with the turret 21 is a pair of conventional muller wheels 40. The muller wheels are pivotally mounted on the turret 21 by means of support arms 4| which have sleeve portions 42 pivotally mounted on axles 43 carried by the sleeve portions 29 and l33 of the turret. The support arms 4l also include an inwardly projecting arm 44 integrally formed on the support arms 4| and abutting at their inner ends on shims 43, Figure 2, positioned on a shoulder portion 45 of the turret 21 to limit the downward pivoting of the muller wheels. An inner sleeve portion 41 of each support arm is arranged to receive a muller wheel shaft 48 about which the muller wheels 40. revolve as the turret rotates.

T remove material from the crib there is provided a discharge door l in the floor of the crib. The door may conveniently be made in the shape of a sector of a circle, fitting in a closed position into a mating opening 52 in the wear plate I8. The door is opened by pivoting it on a hinge 53 by means of a handle54. When the door is opened, rotation of the plow and scraper will cause material to be pushed through the door opening.

In accordance with the teachings of this invention, a tubular post 60 is mounted over thc vertical drive shaft 23 with an apertured end closure plate 5l disposed over the reduced threaded upper end of the shaft 23, and held thereon by a washer 63 and lock nut 64. A bracket 66, secured across the upper end of the post 60, as by welding, is provided with depending arms 88 on the bottom surface thereof. A uid actuated power cylinder 1D is pivotally connected on a pin 1| through each of the arms 68 having a piston rod 13 extending directly downwardly for pivotal connection with the arm 44 of the muller therebelow.

It is to be particularly noted that the piston rods 13 exert a substantially straight vertical thrust on the arms 44 and that the arms 44 are attached directly to the rocker arms 4l substantially at the hub portions of the mullers. Thus the thrust from the power cylinders is applied through the muller wheels to the material being processed in the crib.

Power is supplied to the fluid cylinder by means of a fluid tight revolving joint 16 of any standard construction, which permits a portion of the joint in the bracket 65 to revolve with the bracket while the supply line 11 thereabove remains stationary. A supply line 18 inside the tube 60 delivers the huid, either a gas or a liquid, to a control box 80 which is also conveniently 4, mounted alongside the tubular extension bolt 60. Since the power cylinders 10 are double acting, supply lines 82 direct fluid to the top of each cylinder while supply lines 83 deliver Iluid to the bottom of each cylinder. It will be understood, of course, that the standard valve arrangements necessary for the operation of a double-acting cylinder will be incorporated in the control box 80.

The selective delivery of nuid under pressure to the various supply lines may be controlled by an electrically operated valve member (not shown) which is energized by electrical supply lines 84 and 85 through a rotating commutator (not shown).

The control box, the electrically operated valve and the commutator may be of any standard commercial design.

From the foregoing description it will be recognized that there is provided in this invention a simple, eiiicient means for varying the unit mulling pressure exerted on material being processed in the crib Without using heavy muller wheels which have high inertia values.

In operation, when pressure is applied to the topV of the power cylinder 1D it will be transmitted to the material in any predetermined quantity up to the limit of capacity of the cylinders.

When pressure is applied to the bottom of the cylinders the piston rods 13, through their pivotal connection to the limit arms 44, will pivot the muller wheels away from the wear plate of the crib thus substantially lessening the pressure exerted thereon.

It is contemplated that the device of the present invention will be used for processing materials ywhich at some stage during the process reach a consistency where either heavy unit pressures are not desirable or the heavy mullers with high values will not turn.l It is possible, with the arrangement described above, to raise the mullers during the initial stage, sov that a simple mixing action by the plows is obtained. At the proper time the mullers could be allowed to bear on the material with increasing pressure until the maximum desired unit pressure is reached. This arrangement would be particularly desirable for materials such as foundry oil bonded core sand, wall paper coatings, air floated clay, and the like.

It will, of course, be understood that various details of construction may be varied through a wide -range without departing from the principles of this invention, and it is, therefore, not the purpose t0 limit the patent granted hereon otherwise than necessitated by the scope of the appended claim.

I claim as my invention:

A muller comprising a crib, a housing extending upwardly through the center of said crib, a turret rotatably mounted on the top of said housing and projecting upwardly therefrom, power means beneath Vsaid crib for rotatably driving said turret, parallel horizontal sleeve members spaced outwardly from opposite sides of said turret and forming a part thereof for rotation therewith, oppositely projecting axles carried by said sleeve members, a wheel support arm pivotally mounted en each of said axles and extending inwardly therefrom along said turret, a muller wheel axle mounted on the free end of each of said wheel supporting arms and extending outwardly therefrom, muller wheels rotatably mounted Von each of said last mentioned axles for rotation about parallel spaced axes adjacent but on opposite sides of a diametral line intersecting the center of said turret and moved about said crib by rotation of said turret, a bracket on said turret above said larms and extending in opposite directions, a separate double acting fluid pressure cylinder pivotally connected to said bracket adjacent each end thereof and depending therefrom, actuating rods depending from said cylinders for extension or retraction with respect thereto upon the admission of iiuid under pressure to one end or the other of said cylinder, said Wheel supporting arms having connecting arms projecting inwardly therefrom ytoward. said turret, and pivotal connections between said actuating rods and said inwardly projecting connecting arms. 1

ROBERT L. MCILVAINE.

6 REFERENCES CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS`

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