US3346200A

US3346200A - Vibrating mill

Info

Publication number: US3346200A
Application number: US462308A
Authority: US
Inventors: Lesin Abram Davidovich; Leibman Leonid Meerovich
Original assignee: VNII STR MATERIALOV
Current assignee: VNII STR MATERIALOV; VSESOJUZNY NAUCHNO-ISSLEDOVATELSKY INSTITUTE STROITELNYKH MATERIALOV
Priority date: 1965-06-08
Filing date: 1965-06-08
Publication date: 1967-10-10
Anticipated expiration: 1984-10-10

Description

Oct. 10, 1967 A. D. LESIN ETAL 3,346,200

VIBRATING MILL Filed June 8, 1965 2 Sheets-Sheet l Oct. 10,1967

VIBRATING MILL Filed June a, 1965 A. D. LESIN ET ALv 2 Sheets-Sheet a FIG. 7

United States Patent Ofifice 3,346,200 Patented Oct. 10, 1967 3,346,200 VIBRATING MILL Abram Davidovich Lesin and Leonid Meerovich Leibmau,

Moscow, U.S.S.R., assignors to Vsesojuzny Nanchno- Issledovatelsky Institute Stroitelnykh Materialov, Moscow, U.S.S.R.

Filed June 8, 1965, Ser. No. 462,398 6 Claims. (Cl. 241171) ABSTRACT OF THE DISCLOSURE A two-chamber vibrating mill having inertial vibrators arranged between said chambers provided with discharg ing hatches for maintaining in grinding chambers the level of material being ground, self-contained air-tight bearing units, sliding bearings with journals so shaped that by the circumference of the journals bearing surfaces are left, a brake mounted on the shaft of the vibrator and a clutch disconnecting the shafts of the vibrator and motor.

The invention relates to vibrating mills used for grinding, homogenizing and mixing solid materials, including abrasives, ores, building materials, chemicals, metals, oxides, ingredients of ceramics and a number of other materials.

Known in the art are vibrating mills incorporating one or several grinding chambers operated by inertial vibrators, e.g. one-chamber mills provided with a vibrator arranged in the case inside the chamber; two-chamber mills with an inertial or eccentric vibrator arranged between the chambers; one-chamber or two-chamber mills provided with two vibrators located outside the grinding chambers.

In conventional mills the discharging hatch provided on the end of the grinding chamber or on the shell does not assure maintenance of the required quantity of material being ground, nor does it ensure a free access to the discharging grate for inspection and cleaning. Further, when replacing the bearings, the vibrator has to be dismounted and re-assembled under workshop conditions, which does not ensure the required cleanness of mounting.

The large resonance amplitudes of vibratory parts in the mill may prove detrimental for the elastic support. In the known mills, if the number of revolutions coincides with the natural frequency of vibrations free vibrations are damped by means of limiters, the mounting of which presents a problem in vibrating machines With a great mass of vibratory units.

The use of sliding bearings in powerful vibrating machines having a great number of revolutions is hampered by the change of the face vector position when starting or stopping the machine as it has to pass over the range of the natural frequency of vibrations.

A main object of the present invention is to increase the efiiciency of vibrating mills.

Another object of this invention is to maintain the required quantity of material bein ground in the grinding chambers and to ensure free access to the discharging grate without causing misadjustment.

Still another object of the invention is to reduce the time necessary for the replacement of bearings and to provide airtightness of the bearing unit in case assemblage to be carried out in the workshop.

It is a further object of the proposed invention to use sliding hearings in high-power machines with a great number of revolutions, the use of conventional rolling contact bearings in such machines being impossible.

Still further object of the invention is to reduce the resonance amplitudes of the vibratory parts of the mill.

Therefore, the primary object of the invention is to develop a highly efficient vibrating mill ensuring the maintenance of a required quantity of material being ground in the grinding chambers, free access to the discharging grate air-tightness of the bearing unit when carrying out assemblage under workship conditions and reduction of resonance amplitudes of vibration.

According to the present invention said objects are achieved by the two-chamber vibrating mill, with inertial vibrators arranged between said chambers being provided assemblage under workshop conditions and reduction of in the grinding chambers the level of material being ground; self-contained air-tight bearing units; sliding bearings with journals shaped so that by the circumference of with discharging hatches making it possible to maintain said journals bearing surfaces are left, said bearing surchange of the phase angle; a brake mounted on the shaft of the vibrator; and a clutch disconnecting the shafts of the vibrator and the motor.

In order that the nature of the invention and the efficiency thereof may be more readily understood, a further description is made with reference to the accompanying drawings, which are sectional views of the vibratin g mill and its components and in which:

FIG. 1 is a side view of the vibrating mill;

FIG. 2 is a top view of the vibrating mill;

FIG. 3 is an end view of the vibrating mill on arrow A;

FIG. 4 is an end sectional view of the discharging hatch taken on line BB;

FIG. 5 is a sectional view of the discharging hatch taken on line C-C;

FIG. 6 is a longitudinal sectional view of the bearing unit with a rolling contact bearing;

FIGS. 7 and 8 are longitudinal and end sectional views respectively of the bearing unit with a sliding contact bearing.

The vibrating mill as shown in FIGS. 1, 2 and 3 consists of two grinding chambers 1 and 2 linked by traverses 3 and 4; inertial vibrators 5 arranged between the grinding chambers; coupling 6; intermediate shaft 7 on bearings 8; brake 9 mounted on the shaft of the drive (vibrator); clutch 1b; motor 11; elastic support 12; and vibration limiter 13.

Each grinding chamber is provided with charging branch pipe 14, discharging hatch 15 and, if necessary, with air feed back pipe 16.

The discharging hatch as shown in FIG. 4 and FIG. 5 consists of two boxes inserted one into the other. Mounted on the external box is outlet branch pipe 17. The internal box is provided with windows in the side walls and the bottom. The size of said windows is adjusted by shutters 18 made as rectangular plates, and by shutter 19 in the form of a swivel disc with holes, said disc changing the size of the outlet port. Mounted on the rear side of the box is cover 21 which provides for the inspection and cleaning of discharging grate 20 without affecting the set position of shutters 18.

The bearing unit (FIG. 6) consists of case 22, hearing 23, covers 24, bush 25, seal 26, and limiting rings 27. Bush 25 is provided with a key-groove for transmitting the torque from the shaft of the vibrator.

Both rolling contact bearings and sliding bearings may be used in the bearing units of the vibrator. The sliding bearings used in the inertial vibrators (FIG. 7) feature a special shape of shaft journal 28, the latter being characterized by the provision of sufficiently developed bearing surfaces, i.e. belts b, the lubricant being supplied in a two-way manner through the shaft into space k.

When the vibrator shaft rotates, the grinding chambers move over a trajectory close to a circular one. The moving walls of the grinding chambers bring the particles of the material under treatment and the grinding bodies into motion. The particles colliding, there arise mechanical stresses which cause disintegration of the particles and wearing of the grinding bodies.

The intensive circular movement ensures homogenizing and mixing of the product consisting of several components. In the continuous process of grinding the material is fed into the grinding chambers through the charging hatches and is discharged through the discharging hatches. The ground material supplied from the grinding chamber through the grate into the space confined by the internal box, fills it up to the upper edge of the shutter and then flows over into the space confined by the external box to be discharged through the outlet branch pipe. The bottom of the internal box is provided with a window for unloading the mill and preventing clogging of the internal box with the ground material adhered thereto, the size of said window being adjusted by the shutter in the form of a swivel disc with holes.

When the mill stops, the clutch disconnects the rotor of the motor from the intermediate shaft at the number of revolutions being somewhat higher than the natural frequency, the brake being engaged simultaneously.

The above mentioned device ensures stopping of the shaft of the vibrator and, thus, quick passing over the natural frequency range whereby a reduction of the resonance amplitude is eifected.

When replacing the bearings, the bearing unit is removed from the vibrating mill and replacement or repair of the bearings is carried out under conditions lit for reassembly.

Thus, cleanness of the bearing unit is preserved and the utilization coeflicient of the machine is increased.

What is claimed is:

1. A vibrating mill comprising in combination at least two chambers with charging hatches, said chambers resting on elastic supports; at least one vibrator mounted in hearings on a drive shaft between said chambers; a discharging hatch built in each of the said chambers and composed of internal and external boxes inserted one into the other, the side walls and the bottom of said boxes forming a space for directing the material for discharging; an outlet branch pipe provided in the external box; windows provided at least in one of the side walls of the said internal box; at least one window provided in the bottom of the said internal box and means for adjusting the size of the windows in the said side walls and bottom of the internal box.

2. A vibrating mill comprising in combination at least two chambers with charging hatches, said chambers resting on elastic supports; at least one vibrator mounted in bearings on a drive shaft between said chambers; a discharging hatch built in each of the said chambers and composed of internal and external boxes inserted one into the other, the side walls and the bottom of said boxes forming a space for directing the material for discharging; an outlet branch pipe provided in the external box; windows provided at least in one of the side walls of the said internal box; at least one window provided in the bottom of the said internal box and shutters for adjusting the size of the windows in the said side walls and bottom of the internal box.

3. A vibrating mill comprising in combination at least two chambers with charging hatches, said chambers resting on elastic supports; at least one vibrator mounted in bearings on a drive shaft between said chambers, the hearing of the said vibrator being freely mounted on sealing bushes; a discharging hatch built in each of the said chambers and composed of internal and external boxes inserted one into the other, the side walls and the bottom of said boxes forming a space for directing the material for discharging; an outlet branch pipe provided in the external box; windows provided at least in one of the side walls of the said internal box; at least one window provided in the bottom of the said internal box and shutters for adjusting the size of the windows in the said side walls and bottom of the internal box.

4. A vibrating mill comprising in combination at least two chambers with charging hatches, said chambers resting on elastic supports; at least one vibrator mounted in bearings on a drive shaft between said chambers; in case of sliding bearings being used the journal thereof is shaped so as to form two clearances between said journal and a brass at an angle to the direction of the acting force, said clearances ensuring a two-way supply of oil from inside the shaft, said journal being provided all over its circumference with supporting belts for transmitting the forces developed by the vibrator; a discharging hatch built in each of the said chambers and composed of internal and external boxes inserted one into the other, the side walls and the bottom of said boxes forming a space for directing the material for discharging; an outlet branch pipe pro vided in the external box; windows provided at least in one of the side walls of the said internal box; at least one window provided in the bottom of the said internal box and shutters for adjusting the size of the windows in the said side walls and bottom of the internal box.

5. A vibrating mill comprising in combination at least two chambers with charging hatches, said chambers resting on elastic supports; at least one vibrator mounted in hearings on a drive shaft between said chambers, the said drive shaft of the vibrator being provided with a disconnecting clutch; a discharging hatch built in each of the said chambers and composed of internal and external boxes inserted one into the other, the side walls and the bottom of said boxes forming a space for directing the material for discharging; an outlet branch pipe provided in the external box; windows provided at least in one of the side walls of the said internal box; at least one window provided in the bottom of the said internal box and shutters for adjusting the size of the Windows in the said side walls and bottom of the internal box.

6. A vibrating mill comprising in combination at least two chambers with charging hatches, said chambers resting on elastic supports; at least one vibrator mounted in bearings on a drive shaft between said chambers, the said drive shaft of the vibrator being provided with a disconnecting clutch and a braking device; a discharging hatch built in each of the said chambers and composed of internal and external boxes inserted one into the other, the side walls and the bottom of said boxes forming a space for directing the material for discharging; an outlet branch pipe provided in the external box; windows provided at least in one of the side walls of the said internal box; at least one window provided in the bottom of the said internal box and shutters for adjusting the size of the windows in the said side walls and bottom of the internal box.

No references cited.

WILLIAM W. DYER, 111., Primary Examiner.

l-iARRY F. PEPPER, 1a., Examiner

Claims

1. A VIBRATING MILL COMPRISING IN COMBINATION AT LEAST TWO CHAMBERS WITH CHARGING HATCHES, SAID CHAMBERS RESTING ON ELASTIC SUPPORTS; AT LEAST ONE VIBRATOR MOUNTED IN BEARINGS ON A DRIVE SHAFT BETWEEN SAID CHAMBERS; A DISCHARGING HATCH BUILT IN EACH OF THE SAID CHAMBERS AND COMPOSED OF INTERNAL AND EXTERNAL BOXES INSERTED ONE INTO THE OTHER, THE SIDE WALLS AND THE BOTTOM OF SAID BOXES FORMING A SPACE FOR DIRECTING THE MATERIAL FOR DISCHARGING; AN OUTLET BRANCH PIPE PROVIDED IN THE EXTERNAL BOX; WINDOWS PROVIDED AT LEAST IN ONE OF THE SIDE WALLS OF THE SAID INTERNAL BOX; AT LEAST ONE WINDOW PROVIDED IN THE BOTTOM OF THE SAID INTERNAL BOX AND MEANS FOR ADJUSTING THE SIZE OF THE WINDOWS IN THE SAID SIDE WALLS AND BOTTOM OF THE INTERNAL BOX.