US2306983A - Hammer mill - Google Patents

Description

HAMMER MILL Filed Jan. 11, 1941 Wk m n mmC E Nssm E 0 ms n ma A Tm CH w WM Patented Dec. 29, 1942 UNITED STATES PATENT OFFW HAIVIMEB MILL Charles F. Schutte and Herman D. Schutte, Snyder, N. Y., assignors of one-fifth to Nellie D. Schutte, Snyder, N. Y.

Application January 11, 1941, Serial No. 374,100

..- a pair of arms it which are arranged in parallel 1 Claim.

This invention relates to hammer mills, and more particularly to hammers for grinding, crushing and pulverizing machines.

We are aware that certain hammer mills of the prior art have been provided with hammer head elements adapted to be adjusted to' different positions so that as certain striking faces become worn other striking faces may be brought into play, so as to prolong the efiectiveness of the hammer heads and to reduce the number of replacements thereof. However, the hammer heads of the prior art and the connection means therefor have been subject to certain serious objections and disadvantages, and it is one object of the present invention to provide an improved hammer and hammer head construction and adjustable connection means therefor which will avoid the disadvantages and objections of the prior art. Another object of the invention is to provide an improved mill construction of the type comprising a combination hammer and hammer head whereby each hammer head is adapted to be mounted upon the corresponding hammer in selected positions, in an improved manner. Another object of the invention is to provide an improved form of hammer head for hammer mills of the character described. Another object is to provide an improved method and means for detachably mounting hammer heads upon hammer mill elements. Other objects and advantages will appear from the specification hereinafter.

In the drawing:

Fig. 1 is a fragmentary side elevation of a hammer mill rotor having a hammer and hammer head of the invention mounted thereon;

Fig. 2 is an end view of Fig. 1 with portions of the connection means thereof shown in section;

Fig. 3 is a view corresponding to Fig. 2 showing another form of means for mounting the hammer head upon the hammer;

Fig. 4 is a section, on a reduced scale, taken substantially along line IV-IV of Fig. 3;

Fig. 5 is a perspective of the hammer head connection device of Fig. 3 shown in disassembled relation therefrom; and

Fig. 6 is a View corresponding to Fig. 3 of another species of hammer head connecting means.

The drawing illustrates the invention in connection with a rotor ll] of a hammer mill which may be generally of any presently known type. A two-piece hammer unit designated generally by the numeral I2 is pivotally mounted upon the rotor II] by means of a pin l4, and comprises relation to extend radially of the rotor 10 from the region of their pivotal connections upon the pin l4. At their outer ends the arms it embrace the hammer head which is designated generally by the numeral 20, and the hammer head 20 is rotatably mounted upon a transverse pin. 22 extending through and between the arms IS; the pin 22 being threadedat each end into connection with suitably threaded openings in the arms 16 by rotational movements of the respective arms about the pin prior to assembly of the hammer arm unit upon the rotor til by means of the pin 14. p

The hammer head 20 is shaped at its peripheral portion with a series of alternating large and small projections 24 and 25, respectively; the projections being circumferentially spaced to provide recesses .28 therebetween. The relatively larger projections 2d are not only greater in radially extending dimension but they are also greater in circumferential extent when compared with the smaller projections 26. Thus, the recesses 28 are relatively grouped in pairs between adjacent of the larger projections 24. The hammer arms l6 are perforated at 30 and 32 so as to register with the corresponding recesses 28 of any pair thereof; and a blind screw 34 or other similar detachable connection device is arranged in connected relation upon the hammer arms and the hammer head to fix the hammer head 20 against rotation in any desired position of adjustment thereon.

For example, the hammer head 20 may be positioned relative to the hammer l2 as shown in Fig. l, and upon wearing away of certain of the projecting portions of the hammer head during operation of the mill, the hammer head may be rotated in either direction to successive positions of adjustment involving 72 of rotation from each preceding position whereby one of the larger projections 24 will always be disposed in line with the longitudinal axis of the hammer unit l2, as in Fig. 1. It will be understood, however, that in lieu of the specific number of projections shown in Fig. 1 in connection with the hammer head thereof, the hammer head may be formed with any other desired number of projections at the peripheral portion thereof, and that the angular rotation required to present unworn projections in line with the longitudinal axis of the hammer arm I2 will depend upon the number of the projections in any given instance and the radial angle therebetween.

It will be understood that upon wearing away of the leading edge portions of the hammer head member 2% subsequent to successive adjustments thereof so that each of the larger projections 24 will have been worn away at corresponding face portions in connection with rotation of the hammer mili unit in one direction of operation, the hammer assembly may be removed and reinstalled in reversely faced relation so that the formerly trailing face portions of the projections 25 become the leading face portions thereof in view of the direction of rotation of the mill rotor mechanism. Thus, ten difierent wearing faces may be successively presented by the hammer head for working purposes. Particular attention is called to the fact that each hammer arm I6 is provided with an aperture 36 and an aperature 32, and that only the apertures 36. are threaded.

The blind screw 34 is threaded only at its innermost end portion, whereby the screw fits'fr'eely into the aperture 32 in either of the plates I6 and into a registering recessed portion 28 of the hammer head and then is screwthreaded into connected relation with the apertured portion 30 of the oppositely disposed plate member l5. Due to the identical form of the opposite plate members [6, the screw 34 may be inserted from either side of the hammer and the plates l6 are entirely interchangeable. Thus, possible confusion in connection with original assembly or replacement of the plates in connection with repair of the mill is avoided. Thus, it will be seen that a novel form of hammer and hammer head is provided whereby a novel adjustability of improved order is obtained.

Figs. 3 to 6 illustrate other forms of hammer head connection means which are embodied as integral portions of the hammer head supporting pin elements. The form illustrated in Figs. 3, 4 and include a hammer head 46 mounted between opposed hammer arms 42 by means of a bolt 44 which is headed at one end and is of angular shank form at 46 so as to be adapted to fit in keyed relation within complementary angularly shaped openings through the hammer head 49 and the hammer arms 42, so as to rigidly mount the hammer head 46 upon the arms 42 against rotation about the axis of the bolt 44. A look washer 38 and a nut 49 are provided at the outer end of the bolt 44 to fix the latter against accidental disengagement from mounting connection. For this purpose the shank 46 of the bolt is threaded as at 55 so as to adapt it to receive the nut in firmly connected relation.

Fig. 6 illustrates another form of hammer and hammer head connection, wherein the hammer head 52 is mounted between opposed hammer arms 54 by means of a bolt 56 which is provided with an angularly shaped shank portion 58 which extends through complementary shaped openings in the hammer arm and hammer head memhead 52 relativeto'the hammer arms 54.

bers so as to firmly key the hammer head against rotation relative to the hammer arms 54. A detachable locking stud 60 is provided at the opposite end of the bolt 56 to fix the latter against accidental displacement from the unit. The stud 6|] is formed with a reduced shoulder 62 extending in freely rotatable relation within the adjacent hammer arm 54 and a further reduced extending stub portion 64 which is threaded for detachable engagement with a bored portion of the bolt 56. Thus, upon threading of the stud 60 into the bolt 56 the unit is fixed in assembled relation in such manner as to prevent rotation of the hammer Preferably a lock washer'fifi will be employed in conjunction with the bolt-stud assembly to prevent accidental disengagement thereof. Or in the alternative, the reduced shoulder portion 62 of thestud 66 may be of angular sectional form and fixed against rotationwithin the adjacent arm 36, and the hammer head and arm unit may be assembled prior to mounting upon the rotor In as in the manner explained hereinabove in connection with assembly of the hammer unit of Figs. 1 and 2.

Thus, novel and a simplified and otherwise improved hammer head means and adjustable connection means therefore have been provided, and it will be understood that although only a limited number of forms of the invention have been shown and described in detail, it will be apparent to those skilled in the art that the invention is not so limited but that various changes may be made therein without departing from the spirit of the invention or the scope of the appended claim.

We claim:

In a hammer mill having a rotor and a pair of I radially extending arms thereon, a hammer head arranged in relatively closely spaced pairs, each of said arms being identical with the other and having a pair of openings therein in registry with said recesses, one of the recesses in each arm being threaded to receive a screw and the other opening being formed'to receive the head portion of a screw, the threaded opening of each arm being in registry with the head receiving opening of the other arm, and screw connection means engaging the threaded opening of either arm and the head receiving opening of the other whereby the periphery of the intermediate portion of said screw means is in abutment with a hammer head port-ion.

CHARLES F. SCHUTTE.

HERMAN D. SCHUTTE.

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