US1944928A - Crushing mill - Google Patents

Description

M. B. DAVIS CRUSHING MILL Jan. 30, 1934.

Filed March 18, 1929 4 Sheets-Sheet l agdi .5

M. B. DAVIS CRUSHING MILL Jan. 30, 1934.

Filed March 18. 1929 4 Sheets-Sheet 2 Jan. 30, 1934. M. B. DAVIS CRUSHING MILL Filed March 18, 1929 4 Sheets-Sheet 3 M JZ/peEW Q50]? a0 i/zwan z fi wai a Patented Jan. 3%, i934 FH'ATES CRUSHING MILL Mason B. Davis, Kendrick, Fla.

Application March 18, 1929. Serial No. 347,806

4 Claims. (01. 83-53) This invention relates to crushing and pulverizing apparatus and appliances and is illustrated herein as embodied in a crushing mill of the single roller type.

Such crushing mills comprise generally a rotary crushing roll and a breaker plate mounted in near proximity to the crushing roll and arranged to serve as a backing member or dam for presenting material to the crushing roll during I rotation of the latter. The breaker plate is customarily spaced from the crushing roll to provide a passageway between the two and is disposed in such a manner relatively to the roll that the cross-sectional area of the passageway decreases downwardly. By means of such a provision, material to be crushed or pulverized may be introduced at the wide upper portion of the passageway and as it flows downwardly, it will be moved in the direction of the crushing roll in order that particles of all sizes will be presented to the action of the roll. Heretofore, it has been generally customary to make the load engaging surface of the breaker plate of a horizontally convex formation and to extend the lower portion of the plate beneath the crushing roll. Furthermore, it has been customary to mount the breaker plates of the prior art in such a manner that they are free to yield upon a certain amount of pressure being applied to them. The purpose of the yielding action vis to prevent breakage of the parts of the mill in the event that a heavy and particularly tough piece of material is introduced between the breaker plate and the roll.

While the prior art devices are doubtlessly satisfactory in operation and in performing the duties for which they are intended, it is an object of the present invention to provide an improved single roll crushing mill that is of such a strong and durable character that the breaker plate will effectively resist all working strains or stresses that are imparted to it, although the plate is rigidly mounted and is not permitted to yield under any conditions.

It is pointed out, however, that although an important object of the invention is as outlined above there are many important features and aspects of the invention which are applicable to crushing mills of the type now generally employed as well as to the heavy and strong mill of the type disclosed in the present application.

In carrying out the above recited object of the invention, it was first necessary to obtain a breaker plate having a load engaging surface that would effectively and efficiently cooperate with the crushing roll in such a manner as to reduce as far as possible the strains and stresses created by the crushing operation. It is accordingly an important feature of the invention to disclose for such purpose a breakerplate, the load engaging surface of which is plain and flat and is disposed with its upper edge more remote from the crushing roll than is its lower edge. Although such flat plain surfaces have heretofore been employed in crushing soft objects or in guiding material to a crusher, it is believed that the present applicant is the first to employ such a surface in connection with a heavy durable crushing mill of the type under discussion.

Another important feature of the invention consists in the provision of an improved means for maintaining the breaker plate in a fixed position relatively to the crushing roll. As illustrated herein, this improved means consists in the provision of interengaging portions formed on the base of the breaker plate and on the support upon which the breaker plate is mounted. These interengaging projections may conveniently take the form of serrations in order that the breaker plate may be adjusted relatively to the rotary crushing roll, and it is contemplated providing additional means for clamping the breaker plate securely in a desired position of adjustment so that it will under no conditions yield or move during the crushing operation.

Still another important feature of the invention, which is conducive to the accomplishment of the recited object consists in mounting the breaker plateand base in such a manner that the plate may be replaced relatively to the base; Thus, in the operation of the will if a breaker. plate subjected to undue stress should crack or break it may be replaced without going to the necessity of replacing the heavy and more or less expensive base in connection with which the plate is employed.

It is customary in crushing mills of the type under discussion to provide the crushing roll with a plurality of slugger knobs which extend outwardly from the periphery of the roll and are utilized in striking and crushing the material being operated upon. It is to be realized that in a construction of the type here under discussion the slugger knobs must be mounted in'an extremely strong and rigid manner and in theprovision of such a mounting there resides another important feature of the invention.

In the illustrated embodiment of the invention the slugger knobs are wedged against circumferential movement in a direction opposite to the direction of the rotation of the roll, whereby the knobs are driven more tightly home each time they strike or engage the material to be crushed. In order to prevent radial displacement of the knobs they are dovetailed into circumferential extending slots and the invention contemplates making the slots slightly longer than the interfitting portions of the slugger knobs in order that the knobs may be removed with ease and facility to permit replacement in the event that a knob becomes broken or chipped beyond repair.

Still other objects and features of the invention will become apparent from a reading of the following specification in the light of the accompanying drawings, in which- Figure 1 is a view in side elevation of a single roll crusher having a breaker plate associated therewith;

Figure 2 is a view in side elevation of the single roll crusher and breaker plate shown in Figure 1;

Figure 3 is a top plan view of the crusher and breaker plate of Figure 1;

. Figure 4 is an enlarged fragmentary view showing the manner in which the breaker plate of the preceding figures is mounted;

Figure 5 is a vertical section through the breaker plate and the support therefor;

, Figure 6 is a fragmentary view of the crushing roll showing in top plan a slugger knob;

Figure 7 is a. View in section taken along the line 7-7 of Figure 6;

Figure 8 is a view in section taken along the line 8-8 of Figure 6; and

Figure 9 is a view in side elevation of a slugger knob.

As shown in Figures 1, 2, and 3 of the drawings, the rotary crushing mill comprises, generally speaking, a crushing or pulverizing roll 10 mounted upon a horizontally extending shaft12 for rotation within bearings 14, 16 located at opposite ends of the roll. One end of the shaft 12 is extended through the bearing 14 and has mounted upon its outer extremity a driving gear 18 which meshes with a gear 20 that is in turn driven by a pulley 22 mounted upon a shaft 24.

As will be observed from an inspection of Figures l and 3, the shafts 12 and 24 are mounted in bearings half of which are formed in base or frame members 26, 28 located at opposite sides of the rotary crushing roll and arranged to extend parallel to one another and perpendicularly to the axis of rotation of the roll.

The frame members 26, 28 for supporting the operating shafts 12 and 24 are spaced apart asuitable distance and are mounted, as shown in Figure 1, upon a concrete base C which is provided with a recess D for receiving the lower portion of the pulley 22, a recess E for receiving the lower portion of the driving gear 18, and a recess F for receiving the lower portion of the rotary crushing roll 10.

The crushing roll 10 rotates in a clockwise di rection as shown by the arrow in Figure l and to assist the roll in performing crushing or pulverizing operations, the mill is provided with a sloping breaker plate which in the drawings is indicated generally by the reference character 30. The breaker plate is made up in two separate pieces which comprise a base member 32 and a load engaging member 34. As illustrated in Figure 5 the base member in vertical crosssection is approximately triangular in shape although the triangularity of the member is really dependent upon the provision of strengthening ribs 36 that are shown more clearly in Figure 2. (Owing to the provision of these strengthening ribs the base member will be hereinafter considered as approximately triangular in vertical cross-section). It will now be observed that at opposite ends of the base member 32 there are provided integrally formed extensions 38, 40 which are adapted to rest upon the supporting members 26, 28 and be secured thereto by means of bolts or other suitable fasteners 42, 44 which extend through elongated slots formed centrally of the supports 26, 28.

The load engaging member 34, it will be observed, is provided with a flat rectangular outer surface and with a plurality of flanged and reflanged portions or members 46, 48, the upper one of which is illustrated in Figure 5 overhangs the top marginal portion of the base and prevents downward movement of the load engaging member relatively to the stationary base member. In order, however, still further to prevent relative movement between the two parts, there are provided a plurality of bolts or other fasteners 50 which extend through alined openings formed in the base and load engaging member, and by means of these two precautionary provisions all movement between the base 32 and the work engaging member 34 is prohibited.

As will be observed from an inspection of Figure l, the triangularity of the base 32 causes the load engaging member 34 to be disposed obliquely to the vertical, whereby there is provided between the load engaging member and the crushing roll a passageway having an upper widthwise dimension which is indicated in Figure 1 by the reference character a and a lower widthwise dimension that is indicated by the reference character 2). Thus, a tapering passageway is provided between the roll and the breaker plate and the construction is such that the breaker plate is mounted rigidly with respect to the roll whereby all material passing between the two members must be crushed to a desired size before escaping from the passageway into a suitable container or receptacle disposed beneath the lower opening.

In order to vary and to control the dimensions of the passageway between the breaker plate and the roll, the mill is provided with means for affording relative adjustment between the two parts and to this end the laterally extending projections 38, 40 formed on opposite ends of the base mem ber 32 merge at their lower portions into horizontally extending braces 52, 54 that are provided on their lower surfaces with serrations 56 (Figures 1 and 4) that engage serrations 58 formed on the base members 26, 28. By virtue of these interengaging serrations or projections the bolts 42, 44 may be loosened and the breaker plate adjusted along the base members 26 and 28 to a desired position and thereafter the bolts 42 and 44 tightened rigidly to fix the breaker plate in the position of desired adjustment. In order to obtain a more fine and precise adjustment of the breaker plate along the supports 26 and 28 the pitches of the serrations carried respectively by the supports or the breaker plate may be, as shown in Figure 4, of different dimensions. Thus, it will be seen that the breaker plate is provided with means for governing its adjustment relatively to the crushing roll, and the lock nuts 42, 44 constitute separate means for fixing the adjustment of the plate.

In the event that it is desired to change the degree of inclination of the load engaging member 34 relatively to the crushing roll 10, the former member may be made of graduated thickness, for xampl as shown in Figure 5, the top cross-sec- I v the direction of tional portion of the member is thicker than the lower cross-sectional portion, whereby the degree of inclination is less than it would be if the member were of uniform thickness. So when. it is desired to change the degree of inclination, it. is necessary only to. interchange one load engaging member with another and the interchangeability of the members constitutes an important aspect of the invention, for, apart from the inclination idea it may be that in a heavy duty mill of this character the load engaging member will become broken or distorted to such an extent as to render it inoperative in which event it may easily be replaced by an intact member.

Another important aspect of the invention as illustrated herein consists in making the load engaging member of a reversible character. Thus, as illustrated in Figures 1 and 5, the lower portion of the member is formed with a flanged and refianged portion 48 as well as the upper portion and with such a provision, the holes for the reception of the bolts 50 being midway of the height, the member may be removed and replaced with the lower extremity disposed in the same position formerly occupied by the upper portion. A reversal of this character also changes the degree of inclination of the breaker plate.

It has been pointed out that in the operation of this mill, in which the breaker plate cannot yield, that severe strains and stresses are imparted not only to the plate but to the slugger knobs with which the crushing roll is, as usual, provided, and in order that these knobs will withstand the severe strains to which they are subjected without becoming loose and falling from the crushing roll there has been provided a new method or arrangement for holding them in place and it is to this that attention will now be directed.

The crushing roll 10 is provided with a multiplicity of recesses located in staggered relation and each of the recesses is shaped to receive a slugger knob. Now turning to Figures 6 to 9 inclusive, it will be observed that each of the recesses is of tapering formation in a direction reverse to the direction of rotation of the roll. Thus, the oppositely disposed side walls 62, 64 of the recesses converge in a rearward direction (which for the sake of convenience will be hereinafter considered as the direction opposite to the rotation of the roll) and the side walls likewise as shown in Figure '7 converge upwardly to form, in toto, a rearwardly tapering dovetailed slot.

Each of the slugger knobs 60 is provided with a body portion which in assembled condition extends outwardly from the periphery of the roll 10, as illustrated, and a base portion 66, which is shaped for interfitting engagement with one of the recesses formed in the roll. The base of each slugger knob is of rearwardly tapering dovetail formation and fits snugly within one of the rearwardly tapering dovetailed recesses. A slot 68 extends transversely across the upward edge of each of the recesses and affords suiiicient room to permit insertion and removal of the slugger knob in the rearwardly extending opening. To the end of preventing accidental escape of the slugger knob, a wedge 70 or other suitable fastening means may be inserted between the forward face of the knob and the forward wall of the slot 68. The slugger knobs 60 are provided at their rearward extremities with portions 72 which overlie the outer surface of the roll 10 and with recesses 74 which may be utilized in loosening the slugger knobs to facilitate their removal.

In operation, it will be seen that as the slugger knobs swing downwardly and strike the material being crushed they are driven more completely home as each blow is struck, and hence they remain in proper position within the roll although they are subject to being removed with ease to permit replacements.

Although the invention has been described herein with particular reference to single roll crushers of the heavy duty type, it is to be appreciated that in many or all of its aspects, it may be incorporated in other rolling mills or in other grinding or pulverizing devices without in the least departing from the scope of the invention as set forth in the appended claims. Furthermore, it is to be understood that the invention contemplates various modifications and changes that will from time to time occur to those skilled in the art and it is to be recognized that such changes come squarely within the terms of the invention as herein set forth.

Having thus described my invention, what I claim as new and desire to secure by United States Letters Patent is:

1. A crushing mill apparatus of the character described comprising, in combination, a breaker plate and a rotary drum-like cylinder having recesses formed in its outer surface arranged for cooperation with the breaker plate, the opposite side walls of said recesses being arranged to converge upwardly and to taper rearwardly, and slugger knobs inserted in the recesses, sm'd slugger knobs comprising body portions projecting outwardly from the recesses, and base portions having their opposite side walls diverging downwardly to interfit with the side walls of the recess and tapering rearwardly also in interfitting relation with the side walls of the recess, whereby the slugger knobs are dovetailed against radial displacement and are wedged against circumferential displacement in a direction reverse to the direction of rotation of the roll.

2. A crushing mill apparatus of the character described comprising, in combination, a breaker plate and a rotary drum-like cylinder having recesses formed in its outer surface arranged for cooperation with the breaker plate, the opposite side walls of said recesses being arranged to converge upwardly and to taper rearwardly, and slugger knobs inserted into the recesses, said slugger knobs comprising body portions of approximately rectangular shape projecting outwardly from the recesses and base portions having their opposite side Walls diverging downwardly in interfitting relation with the side walls of the recess and tapering rearwardly also to interfit with the side walls of the recess whereby the slugger knobs are dovetailed against radial displacement and wedged against circumferential displacement in a direction reverse to the direction of rotation of the roll, the length of said recesses being slightly greater than the length of said base portions to permit insertion and removal of the slugger knobs.

3. In a crusher, a rotary crusher roll having a plurality of recesses formed in its outer sur face, the opposite side walls of each of said recesses being formed to converge radially outward with respect to the roll and to converge circumferentially of the roll in a direction opposite to the direction of rotation of the roll and crusher teeth removably inserted in said recesses, said teeth including portions projecting outwardly with respect to the outer surface of said roll and attaching portions in said recesses, said attaching portions having opposite side walls formed to converge radially outward with respect to said roll and to converge circumferentially of the roll in a direction opposite to the direction of rotation of the roll whereby said teeth are dovetailed against radial displacement and are wedged against circumferential displacement.

4. In a crusher, a rotary crusher roll having a plurality of recesses formed in its outer surface, the opposite side walls of each of said recesses being formed to converge radially outward with respect to the roll and to converge circumferentially of the roll in a direction opposite to the direction of rotation of the roll and crusher teeth removably inserted in said recesses, said teeth including portions projecting outwardly with respect to the outer surface of said roll and attaching portions in said recesses, said attaching portions having opposite side walls formed to converge radially outward with respect to said roll and to converge circumferentially of the roll in a direction opposite to the direction of rotation of the roll whereby said teeth are dovetailed against radial displacement and are wedged against circumferential displacement, the widths of said recesses circumferentially of said roll being slightly greater than the width of said attaching portions of said teeth to permit insertion and removal of said teeth.

' M. B. DAVIS.

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