US1144089A - Attrition-mill plate. - Google Patents

Description

E. P. ALSTED.

ATTRITION MILL PLATE.

APPLICATION FILED DEC. 16. 19l2. 1,144,089;

Patented June 22, 1915. Z 2 SHEETS-SHEET l. 54/ '2 E. P. ALSTED.

ATTR ITION MILL PLATE. APPLICATION FILED DEC. 16, 1912.

1,144,089. Patented June 22, 1915.

' 2 SHEETS-SHEET 2.

EDWARD R'ALSTED, OF TBUESDELL, WISCONSIN.

ATTRITION-MILL PLATE.

Specification of Letters Patent.

Patented June 22, 1915.

Application filed December 16, 1912. Serial No. 736,949.

T aZZ whom it may concern:

Be it known that I, EDWARD P. ALSTED, a citizen of the United States, and resident of Truesdell, in the county of Kenosha and State of Wisconsin, have invented new and useful Improvements in Attrition-Mil] Plates, of which the following is a descrip tion, reference being had to the accompanying drawings, which are a part of this speci' fication.

This invention relates to improvements in attrition mill plates between the opposing faces of which the material to be ground is introduced.

One of the objects of this invention is to provide grinding disk plates for attrition mills in which the material fed between the plates from the inner peripheries thereof is evenly distributed throughout the entire grinding surfaces of the plates thereby preventing uneven wear on the plates and forming a more efficient reducing surface.

A further object of the invention is to provide grinding disk plates for attrition mills with ribs of peculiar configuration which are shaped to distribute the material evenly throughout the entire grinding faces of the plates to prevent uneven wear of said plates.

A further object of the invention is to provide grinding plates for attrition mills in which the pockets of the plates are so positionedwith relation to pockets of opposite plates as to overlap each other and permit material to pass radially from one series of pockets to another.

' With the above and other objects in view, the invention consists of the improved grinding disk plates and their parts and combinations as set forth in the claims, and

all equivalents thereof.

In the accompanying drawings in which the same reference characters indicate the same parts in all of the views:

Figure 1 is a face view of a fragment of a grinding disk provided with the improved grinding face. Fig. 2 is a transverse sectional view thereof taken on line 22 of Fig. 1; Fig. 3 is a face view on a reduced scale of the completed disk; Fig. 4 is a diagrammatic view of one of the'ribs of each opposing disk showing the line of engagement of the material reducing edges and the overlapping of the pockets of opposite plates, one of the ribs being indicated by dotted lines. Fig. 5 is a face view of a fragment of a modified form of disk; Fig. 6 is a transverse sectional View thereof taken on line 66 of Fig. 4; Fig. 7 is a face view of a fragment of another form of disk; and Fig. 8 is a transverse sectional view taken on line 8-8 of Fig. 7.

Referring to the drawings the numeral 10 indicates one of a plurality of segmental grinding plates which are adapted to be fastened to the opposing heads or disks of an attrition mill by means of screws 11 eX- tending through openings 12 provided in said segments and threaded to the disks to form a complete grinding face for said disks. The segmental plates are provided with long, short and intermediate length radial ribs 13, l-t and 15 respectively which are spaced equi-distantly circumferentially on the face of the plate.

The outer ends of the ribs are joined to; gether by an outer concentric rib l6 and the medial portions of the ribs are joined together by a transverse biangular rib 17 which extends approximately heXagonally in form around the face of the assembled plates. Portions of the sides of the hexagonal form are omitted or broken away to provide outlet openings 18 to permit the material to pass freely toward the outer portions of the ribs. These openings are guarded by short ribs 19 which overlap the end portions of the sides and are spaced radially outwardly a short distance beyond the said sides. The radial and other ribs form pockets 20 of various lengths into which the material is fed and is engaged by the edges 21 of the ribs forming said pockets and reduced thereby.

The inner concentric edges 22 of the plates are beveled or rounded of to more freely admit the material into the pockets and the spaces between the radial ribs.

The faces of the ribs at points indicated by the numeral 23 and approximately midway between the inner and outer peripheries of the plates 10 are of less width than the other portions and from these points the rib faces taper radially toward their opposite ends to a greater width to provide a shearing cut between the ribs of opposite plates, so that the line of engagement of the shearing cut will travel from points near the outer and inner peripheries of the plates toward the medial portions thereof. This construction serves to distribute the wear of cutting along the edges of the entire length of the ribs instead of at the outer ends of the ribs as in grinding disks of ordinary construction. 7

As the corner portions 24 of the transverse or biangular extending ribs 17 extend radially beyond the portions forming the.

sides of the hexagonal form, the opposite rotation of the disk will cause the said corners to overlap the opposite side portions of I the material between the plates until it is reduced to the degree of fineness regulated by the spacing of the disks apart.

In the modified form shown in Figs. 5 and 6 radial ribs 25 are provided which are similar to the radial ribs of the principal form and the transverse ribs 26 are of biangular formation and are spaced a greater distance from similar adjacent ribs than in the other form. A series of short ribs 27 guard the spaces between the biangular ribs.

This form of plate is adapted to reduce the material in substantially the same manner as before described and the same description will apply.

In the modified form shown in Figs. 7

I and 8 the biangular rib 28 of each plate joins with the ribs of adjacent plates and forms a continuous rib of approximately star shape and the short ribs 29 while of greater length than theribs of the other forms are similarly positioned with relation to the angular or transverse ribs and are adapted to perform the same function.

This last mentioned modification is provided with ribs on opposite sides of the plate so that when one side is worn the other side may be used. 7

Both sides of all of the ribs are of similar form to provide for double wear by rotating in the opposite direction when the edges extending in one direction are worn.

From the foregoing description it will be seen that the plates are adapted to spread the material over the entire working surface and also that the shearing engagement is extended along the entire length of the ribs thus eliminating wear at one point on each rib.

What I claim as my invention is:

1. Attrition mill plates, comprising oppositely rotatable plates provided with material reducing radial ribs of varying lengths,

the material engaging edges of ribs of opposite plates-diverging toward the axis of the plates when in engagement with each other for a portion of their lengths to advance the line of material engagement in a direction toward the axis of rotation, and transverse ribs extendingin approximately straight short broken lines circumferentially around the medial portions of the faces of the plates, said brokenlines of transverse ribs forming outlet openings permitting the reduced material to work outwardly.

2. Attrition mill plates, comprising oppo- 'sitely rotatable plates provided with material reducing radial ribs of varying lengths and with transverse ribs, the medial face portions of the radial ribs being of less width thantheir opposite end portions to advance-the line of material engagement to ward said medial face portions, the transverse ribs extending in "approximately straight short broken lines which have a shearing engagement with like ribs of op- I posite plates, said broken lines of transverse ribs forming outlet openings permitting the reduced material to work outwardly. V 1

3. A grinding plate for attrition mills, comprising a segmental plate provided with radial ribs of varying lengths, other ribs extending transversely across the radial ribs and also extending approximately in straight short broken lines hexagonally around the face of the plate and short transverse guard ribs overlapping the broken portions of the broken ribs, said broken lines of transverse ribs forming outlet openings permitting the reduced material to work outwardly.

4. A grinding plate for attrition mills provided with material reducing radial ribs of varying lengths and with short angular ribs which extend across the radial ribs at angles other than at right angles, said short ribs forming outlet openings permitting the reduced material to work outwardly.

5. A grinding plate for attrition mills, comprising segmental plates provided with material reducing radial ribs of varying lengths which are of less width medially than at their outer ends, and short biangular ribs extending across the radial ribs, said short ribs forming outlet openings permitting the reduced material .to "work out-' wardly.

6. A grinding plate for attrition mills,

comprising segmental plates provided with ribs, said outlet openings permitting the material reducing radial ribs of varying reduced material to work outwardly. 1o lengths, biangular ribs extending across the In testimony whereof, I affix my signaradial ribs, the ends of said biangular ribs ture, in presence of two witnesses.

being spaced from the ends of similar ad- EDWARD P. ALSTED. jacent ribs to form outlet openings and other Witnesses:

ribs extending across said openings and CHARLES E. TURNOCK,

spaced outwardly from the said biangular LAURA O. BALDWIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. G. V

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