US2460279A

US2460279A - Hammer for impact crushers with detachable and reversible hammer head

Info

Publication number: US2460279A
Application number: US513759A
Authority: US
Inventors: Leslie G Ehmann
Original assignee: Electric Steel Foundry Co
Current assignee: Electric Steel Foundry Co
Priority date: 1943-12-10
Filing date: 1943-12-10
Publication date: 1949-02-01
Anticipated expiration: 1966-02-01

Description

Feb. 1, 1949. 4, a. EH 2,460,279-

- HAMMER FOR IMPACT cnusnsns WITH DETACHABLE AND REVERSIBLE HAMMER HEAD Filed D00. 10, 1943 3 Sheets-Sheet l LE \E q. 2-H

L' G. EHMANN HAMMER FOR IMPA CT CRUSHERS WITH DETACHABLE AND REVERSIBLE HAMMER HEAD Filed Dec. 10, 1943 3 Sheets-Sheet 2 TERA 5% Feb. 1, 1949. L. G. EHMANN 2,460,279

HAMMER FOR IMPACT CRUSHERS WITH DETACHABLE 3 Sheets-Sheet 3 AND REVERSIBLE HAMMER HEAD Filed Dec. 10, 1943 jg; 5. J2

UNITED STATES PATENT OFFICE HAMMER FOR IMPACT CRUSHERS WITH IIJIETACHABLE AND REVERSIBLE HAMMER Leslie G. Ehmann, Portland, reg., assignor to Electric Steel Foundry, Portland, 0reg., a corporation oi Oregon Application December 10, 1943, Serial No. 513,759

10 Claims.

This invention relates to rotary impact crushers of the type commonly used to crush or pulverize rock, coal, cement and similar substances, and.

more specifically to a new and improved hammer tached from the shank during operation of the crusher.

A further object of the invention is to provide a reversible type hammer head so constructed as forusgtherein, to provide for a maximum amount of surface Rotary impact crushers usuall comprise a rotor wear before necessitating replacement. element mounted within a generall cylindrical These and other features-of the invention are cage formed of breaker bars, said rotor element fully described in the following paragraphs, refcomprising a plurality of discs mounted in spaced erence being made to theaccompanying drawings relation on a driven shaft and having a plurality in which: of hammers pivotally attached to the rotor eie- Figure 1 is an end view of the rotor element of ment adjacent the periphery of the discs. The a rotary crusher showing the relative positions of rotor element is driven at high speed and material four rows of hammers of a type embodying the fed thereto is crushed or pulverized between the present invention; Figure 2 is a longitudinal view, hammers and the cage. Each row of hammers approximately on the line 2-2 of Figure 1, of a usually is attached to the rotor element by means portion of a crusher illustrating the arrangement of a single pivot shaft extending through openof a row of hammers therein; Figure 3 is a perings near the periphery of the discs, with the p i e View, p r y n i n, of a hammer hammers mounted on the shaft between the discs. ead; ig 4 is a p spe tive view of a hammer Impact hammers embodying the present inshank s owi t e locking p n b ng assembled; vention are adapted for use in various types and Fi re 5 i a fragm ntary sectional view of a kinds of crushers and reducers, the leading edges hammer shank showing the manner in which the of the hammers being subject to considerable wear h for admitting e locking p is Closed p under impact with the material being crushed. man ntly aft r as m ly t p n sp m nt It becomes desirable, therefore, to periodically ref h p Figure 6 is a perspective view, partly verse the position of the head on the shank to in section, of a hammer embodying the present provide for more even wear of the hammer head, i ve ust ating the same as being mounted and to replace the head portion entirely when in Working p t 0n the Pivot s a t of a rotary worn to such an extent as to make further use crusher; Figure 7 is a pe p View, P y in impractical. w t t various types of hammers section, similar to Figure 6, showing the manner in use heretofore it has been necessary to remove cking the hammer head from the shank the pivot shaft from the rotor element in order to. for reversing replacing the same Without disreverse or replace the head portion of the hamassembling the shank from the pivot shaft; and mer. This operation requires the dismantling of Figures 8v and 9 illustrate a sectional elevation of aconsiderable portion of the machinery comprisa hammer showing a modified construction eming the rotor element, and is the cause of conbodying the invention and the manner of siderable delays in the operation of the crusher, locking the hammer head and usflally l'eqlm'es the use P special tools- In Figures 1 and 2 is shown portions of a rotor In the b an oblect ofthe present element such as used in a crusher of conventional nvention 15 to provide a hammer adapted for use 40 design The rotor comprises a driven shaft '0 1n rotary impact crushers, of which-the head por- .havin a 1 rt f I tion may be reversed or replaced in a minimum g p um I y o lscs mounted. thereon and keyed thereto each of the several discs havlength of time wlthout the use of special tools 1 and without detaching the shank portion of the mg aiuany extgndmg hubrmwns by reason hammer from the shaft which connects it to the of which the dlscs are posltioned on the i rotor assembly. spaced apart relation. Each disc is provided A further object of the invention is to provide afiiacent its Periphery with Openings '3 spaced a reversible type hammer head which may be so ninety degrees apart for reception therethrough attached to the shank portion that none of the of Pivot shafts on Whieh are mounted the stresses imposed upon the head are imparted to Shanks of a plurality of hammers embodying t fastening means I v the instant invention. The hammers are mount- It is a further object of the invention to provide ed between each adjacent two of the discs I I the a. reversible type hammer head which may be s an s extending between the discs for eng detachably secured to the shank portion in such 56 ment with the pivot shafts I4. Each of the manner as to preclude the head becoming deshanks I5 is provided with an eye It for receiving therethrough the pivot shaft ll by which the hammer is secured to the rotor element.

Each of the hammers comprises a shank portion I 3 for attachment to the rotor element in the manner above described, and a head portion 2| detachably fastened to the shank portion by a locking device presently to be described. The shank portion I is of one piece construction and comprises an elongated body of generally rectangular shape having at one end thereof an eye I8 for the reception of the pivot shaft I4 and provided at the opposite end thereof with an elongated slot ll extending transversely through the outer end l8 of the shank, the axis of the slot ill being parallel with the axis of the eye i8. The shank I5 is formed with an enlargement intermediate its ends providing shoulders I8 encircling opposite edges of the shank and facing in the direction of the slotted outer end |8 for insuring a proper seating relation between the head 2| and the shank I5. The outer end l8 of the shank forms a projection extending outwardly from the shoulders i9 and is adapted to be received in a recess 26 in the hammer head 2|.

A bore 22 is provided longitudinally of the shank l5, and mounted within the bore 22 and having free movement longitudinally thereof is a locking pin 28. At the outer end of the shank the bore 22 opens into the slot ll, while at the inner end of the shank the bore 22 opens into the eye 66. The locking pin 23 is made somewhat longer than the length of the bore 22 and projects either into the slot il or into the eye it, as the case may be. The locking pin 23 is not of sufficient length,.however, to project into both the slot il and the eye l6, so that when the end of the pin projects into the slot ii, for example, the opposite end of the pin is received into the body of the shank.

The hammer head 2| comprises a work performing portion 24 positioned away from the shank, and a shank end receivin portion 25 positioned toward the shank and having a central open recess 26 within said shank end receiving portion of such size as to receive therein the slotted end |8 of the shank, whereby the several parts may be assembled into one operating unit. In the construction illustrated in the drawings, the recess 26 is defined by end walls 21 and side walls 28. The

walls

21 and 28 terminate in shoulders 29 which lie in the plane of the inner surface of the hammer head and cooperate with the shoulders I9 on the shank IE to prevent a rocking motion between the shank I5 and the head 2| when in operation. The side walls 23 of'the recess 25 in the hammer head are provided with aligned slots 3| which, when the shank I5 and head 2| are assembled, are in alignment with the slot I! in the end portion |8 of the shank, thus providing a continuous opening extending entirely through the hammer head 2 I. An advantage of this construction lies in the fact that the recess 26 in the hammer head may be relatively shallow, as compared to the work performing portion 24 of the head, and so provides a maximum amount of wearing surface, which reduces operating costs by reason of the longer use of the head before replacement is necessary.

' For lockin the hammer head 2| on the end of the shank I 5 there is provided a key 32 of such shape as to conform to the opening through the hammer head formed by thealigned slots 3| and I! when the hammer head and shank are in assembled relation. The key 32 is provided with a through hole 33 which, when the key is 7 within.

in proper position, is in alignment with the longitudinal bore 22 in the shank I! in which is mounted the locking pin 23. When the key 32 is inserted in the aligned slots 3| and I! the locking pin 23 drops into the through hole 33 in the key and prevents displacement of the key from the aligned slots. In that embodiment of the invention illustrated in Figures 6 and 'I the locking pin 23 is of such length that when the outer end thereof is in engagement with the key 32 the inner end of the pin is flush with the peripheral wall surface of the eye i6 so that the presence of the pivot shaft M, by which the hammers are secured to the rotor element of the crushin device, prevents longitudinal movement of the locking pin in the bore 22, thus insuring against displacement of the key 32. The key, in turn, securely locks the hammer head 2| to the shank i5 and prevents any of the parts becoming displaced during operation of the crusher.

The shank i5 is provided with a transverse bore 3% communicating with the longitudinal bore 22 which provides access to the locking pin 23 in the event accumulations of material in the bore 22 may require manual effort to move the pin.

In Figures 4 and 5 is illustrated the manner of assembling the locking pin 23 in the longitudinal bore 22. When the shank i5 is cast the bore 22 is made to extend through the end l8 of the shank, i. e., through the portion forming the outer wall of the transverse slot ll. Thereupon the lockin pin 23 is placed in the longitudinal bore 22 and the opening in the end of the shank is permanently closed as by welding a plug 30 there- The locking pin is of lesser diameter than the diameter of the bore 22 and has free movement longitudinally therein, the pin being retained in the bore by the plug 30 at the outer end of the shank and by that portion of the inner end of the shank forming the wall of the eye I6.

Figures 6 and 7 illustrate a construction in which the pivot shaft l4, extending longitudinally of the rotor element through aligned openings l3 in spaced discs H, is provided with notches 35 which are spaced longitudinally of the shaft a distance corresponding to the distance between the locking pins 23 in adjacent hammers. Each notch 35 is of sufilcient size to receive therewithin the end of a locking pin 23, and is of such depth that when the inner end of the locking pin 23 drops into the notch 35 the opposite end of the locking pin disengages the key 32, permitting the keyto be removed from the hammer head to permit removal of the head from the shank.

In assembling the hammers in the crusher, each row of hammers is mounted on the rotor element by inserting the pivot shaft i4 alternately through openings l3 in the discs H and through the eyes IS in the shanks l5. With the rotor element rotated to the position illustrated in Figures 6 and '7, wherein the hammers may extend vertically from the rotor element with the hammer head 2| uppermost, the pivot shaft I4 is moved longitudinally of the rotor element to bring the several notches 35 into registry with the longitudinal bores 22 in the shanks l5. In this position the inner end of each locking pin 23 drops into one of the notches 35, thus clearing the slot I! in the outer end of the shank for insertion of the key 32. Thereupon the hammer head 2| is placed on the shank, the end of the shank being received in the recess 26 with the slot H in the end of the shank aligned with the slots 3| in the side walls 28 of the head. Thereupon the key 32 is inserted in the aligned slots 3| and I1 and aeeaare the locking pin 23 is moved longitudinally oi the bore 22 and caused to engage through the hole 33 in the key 32. This movement of the locking pin causes the inner end of the pin to disengage the notch 35 in the pivot shaft, whereupon the pivot shaft i i may be moved into the position shown in Figure 6, in which position the inner end of the locking pin 23 rides upon the outer surface of the shaft it and is prevented from dis engaging the key 32. The shaft it may be secured in the final assembled position by means of a screw 35 extending diametrically from the periphery of the outer disc it into the registering notch 35 in the pivot shaft it.

' At such times as the hammer heads are to be reversed or replaced, or at the time of the initial assembly of the machine, the rotor element might well be rotated to he position shown in Figures 6 and '7 to permit the hammers to extend vertically from the upper side thereof with the heads 2i in the uppermost position. Thereupon the screw 35 is withdrawn from engagement with the outermost notch 35 and the pivot shaft it is moved longitudinally of the rotor element to place the notches 35 in registry with the longitudinal bores 22 in the several shanks i5. When this occurs the locking pins 23 drop into the notches 35 and disengage the keys 32 which may then be removed from the aligned slots 3! and iii to release the hammer heads. The hammer heads may then be either reversed or replaced as required. When the hammers have been reassembled and the key 32 shall have been reinserted in the aligned slots 39 and i'i, the rotor element may be rotated through an angle of 180 degrees to cause the several locking pins 23 to drop into the hole 33 in the key and disengage the several notches 35 in the pivot shaft it. Thereupon the pivot shaft is moved longitudinally of the rotor element to disalign the notches 35 and the longitudirial bores :22 in the shanks i and to bring the outermost notch 35 into registry with the screw 36 which is then turned down to engage the notch to prevent longitudinal movement of the shaft during operation of the device.

Referring now to Figures 8 and 9, there is shown a portion of a rotor element for a rotary crusher comprising spaced discs 37 and a longitudinally extending pivot shaft 38 as in the construction hereinabove described. Mounted on the pivot shaft 35 is shown ahammer embodying the present invention. The hammer comprises a shank 393 having an eye M provided in its inner end for the reception of the pivot shaft 38', and an outer end portion 62 extending outwardly from shoulders #33. The outer end at of the shank is provided with a transverse slot 44 disposed intermediate the plane of the shoulders 43 and the ex treme end surface of the shank. The shank is provided with a longitudinal bore #35 communicating at its outer end with the transverse "slot M. Mounted in the longitudinal bore for free movement longitudinally thereof is a lockin pin 46 adapted for engagement with the key 6? by means of which the hammer head 48 is secured to the shank.

The shank is provided intermediate its ends" which position the

slots #

36 and 56 are in alignment, the key il is inserted in the aligned slots to secure-the head to the shank. The key Wis providedwith a center hole 51? adapted to receive the end of the locking pin 66 to prevent displacement of the key.

The locking pin 36 is of such length as to hear at one end against the outer wall 58 of the transverse slot it in the end of the shank, and to bear at the other end against a shoulder 59 on the screw plug 5i. With the key il inserted in the aligned slots i l and 56, the locking pin 66 enters the hole 5? in the key ti and is held therein by the shoulder 59 on the plug 5i. To release the key ii? the screw plug 5i is backed up sufliciently to withdraw the shoulder 59 from the longitudinal bore #35, whereupon the locking pin (it may drop out of engagement with the key it to permit removal or the key from the aligned slots 63 and 55, thus releasingthe head M The locking pin 38 is chamfered at its outer end to provide a shoulder ti by which the pin may be engaged to withdraw it from engagement with the key in the event an accumulation of dust or other matter may tend to plug the longitudinal bore :35.

in the manufacture or the hammers shown in Figures 8 and9, the shank 39 is cast with the longitudinal bore 45 extending from the eye 5H in the inner end of the shank to the transverse slot tli in the outer end of the shank, the longitudinal bore communicating with both the eye ii and the slot it. It will be noted that the length of the locking pin 416 is slightly less than the diameter of the eye-til, and in assembling the shank the locking pin is inserted in the longitudinal bore 45 through the end thereof which communicates with the eye 6 i. Thereupon the longitudinal bore 65 is plugged at the point of its intersection with the transverse bore 39, as by means of a plug S2, for preventing loss of the locking pin from the longitudinal bore by way of the eye iii. The locking pin is of lesser diameter than the longitudinal bore 65 and is permitted free longitudinal movement therein, being retained therein by means of the plug 62 intermediate the length of the bore, and by the end portion of the shank forming the outer wall of the transverse slot dd.

To reverse or replace a head 48 on a shank 39 the plug 5| is unscrewed from the threads in the end of the transverse bore 49 a suflicient distance to clear the pin 46, whereupon an appropriate tool, or even a finger, may be inserted into the opposite end of the transverse bore $9 to engage under the shoulder 6! on the pin 35 to withdraw the pin from the hole 51 in the key 81. If convenient, the rotor element may be rotated to the position illustrated in Figures 8 and 9 to permit the hammers to extend vertically from the upper side thereof with the heads as in the uppermost position. In such position, when the plug 5| is backed out of the transverse bore 49 the locking pin 46 will drop out of engagement with the key 81 and the key be thereupon removable to release the head as shown in Figure 9. When the head shall have been re- 7 versed orreplaced and the key reinserted in position to engage the aligned

slots

44 and 56, the locking pin may be moved to extend through the hole 51 in the key and the plug II threaded into 'the transverse bore 49 to retain the pin in looking engagement with the key.

- An important advantage of the invention is that it precludes the necessity of disconnecting the shank portion of the hammer from the rotor element when reversing or replacing the head, which permits such repairs to.be made within a minimum period of time and without the use of special tools. A further advantage is that no strain is placed on the locking pin during operation of the crusher, the resulting stresses being absorbed by the key member which locks the head on the shank.

There is herein shown and described a particular embodiment of the invention,- illustrating the principle thereof as applied to a hammer for impact crushers. It will be understood, however, that the invention is applicable to other structures embodying a. releasable fastening means for a detachable part, and that various changes in form, proportion, size and details of construction to without departing from the spirit or sacrificing any of the advantages of the invention.

Having now described my invention and in what manner the same may be used, what I claim as new and desire to protect by Letters Patent is:

1. A hammer for impact crushers comprising a shank, a hammer head replaceably mounted on the end of said shank, said shank comprising an inner end having an eye therethrough for mounting said shank on the pivot shaft of a rotor element in a rotary crusher and an outer end having a slot extending therethrough, a bore extending longitudinally of said shank and opening into said slot, a locking pin disposed in said bore and having free movement longitudinally thereof, the head comprising a work performing portion positioned away from the shank, a shank and receiving portion positioned toward the shank. a central open recess within said latter portion of such size as to receive therein the outer end of said shank, said recess having opposite wall portions, aligned slots extending through said wall portions, the slot in the outer end of said shank being in alignment with the slots in said walls when said shank and head are in assembled relation, '8. key insertable into the opening formed by said slots for locking said head on said shank, a through hole in said key for receiving the end of said locking pin when said key is in said opening, and means movable into engagement with the opposite end of said pin for releasably holding said pin in-engagement with said key.

2. A centrifugal hammer comprising a shank, means adjacent one end of said shank for mounting said shank on the rotor element of a rotary crusher, means defining a slot extending through said shank adjacent the opposite end thereof, a bore extending longitudinally of said shank and opening into said slot, a locking pin disposed in said bore and being movable longitudinally thereof, a hammer head replaceably mounted on the slotted end of said shank comprising a work performing portion positioned away from the shank, a shank end receiving portion positioned toward the shank, a central open recess within said latter portion for receiving therein in closely fitting engagement therewith the slotted end of said shank, said recess having opposite wall por- 'tions, aligned slots extending through said wall portions, the slot in the end of said shank being in alignment with the slots in said walls when the shank and head are in assembled relation, a key insertable into the opening formed by said slots for locking said head on said shank, said locking pin being movable into locking engagement with said key when said key is in said opening, and means for releasably holding said pin in engagement with said key.

3. A centrifugal hammer comprising a shank and a'hammer head replaceably mounted on said shank, upstanding walls on said head defining a recess therebetween, means defining aligned openings extending through said walls, said shank comprising an end portion adapted to be received in said recess between said walls, means defining an opening through the head engaging portion of said shank, a bore disposed longitudinally of said shank extending into said opening, the opening in said shank being in alignment with the opening in said walls when said shank and head are in assembled relation, a key insertable into the opening through said assembled g5 shank and head for locking said head on said within the scope of the claims may be resorted shank, and a pin slidably mounted in said bore and movable into the opening in said shank for engaging said key, and means for releasably holding said pin in engagement with said key.

4. A centrifugal hammer comprising a shank member and a head member replaceabiy mounted thereon, a coupling for detachably locking said members in operative relation, said coupling comprising upstanding walls on one of said members defining a recess therebetween, aligned openings extending through said walls, a portion of the other of said members adapted to be received in said recess between said walls and having an opening extending therethrough, the openings in both said members being in alignment when said members are in assembled relation, a key insertable into said openings, and means carried by said shank member and movable into engagement with said key for releasably holding said key in said openings, said means being shrouded by said shank member and slidable therewithin for movement between positions of engagement and disengagement with said key.

5. A coupling means for detachably coupling separable parts in united operative relation, comprising a part having upstanding walls defining a recess, aligned openings extending through said walls, a second part having an end portion adapted to be received in said recess and having an opening extending therethrough, a bore in said second part extending into said opening, the opening in said second part being in alignment with the openings in said walls when said parts are in assembled operative relation, a key insertable into the opening through said assembled parts for locking said parts in operative relation, and a pin slidably mounted in said bore and movable into engagement with said key for releasably holding said key in said locking position.

6. In a rotary crusher, a rotor element havin a shaft, a plurality of hammers mounted on said shaft, each said hammer comprising a shank and a head replaceably mounted on said shank, said shank and said head having interengaging parts for mounting said head on said shank, means defining openings through each of said interengaging parts, said openings being in alignment when said shank and head are mounted in operative relation, a key insertable in said openinks for detachably locking said head on said shank, means mounted in said shank for holdin said key in said aligned openings, and means mounted in said shank for releasably holding said last named means in engagement with said key. I

7. In a rotary crusher, a rotor element having a shaft, a plurality of hammers mounted on said shaft, each said hammer comprising a shank and a head replaceably mounted on said shank, said shank and said head having interengaging parts for mounting said head on said shank, means defining openings through each of said interengaging parts, said openings being in alignment when said shank and head are mounted in operative relation, 9. key insertable in said openings for detachably locking said head on said" shank, a pin mounted in said shank for holding said key in said aligned openings, and means mounted in said shank for releasably holding said pin in engagement with said key.

8. In a rotary crusher, a rotor element having a. shaft, a plurality of hammers mounted on said shaft, each said hammer comprising a shank and a head replaceably mounted on said shank, said shank and said head having interengaging parts for mounting said head on said shank, means defining openings through each of said interengaging parts, said openings being in alignment when said shank and-head are mounted in operative relation, a key insertable in said openings for locking said headon said shank, a pin mounted in said shank for holding said key in said aligned openings, and means defining a recess in said shaft into which said pin may be moved to release said key, said shaft being movable relative to said rotor element to move the recess in said-shaft into alignment with said pin.

9. In a. rotary crusher, a rotor element having a shaft, a plurality of hammers mounted on said shaft, each said hammer comprising a shank and a head replaceably mounted on said shank, said 10 shank and said head having inter-engaging parts for mounting said head on said shank, means defining openings through each of said interengaging parts, said openings being in alignment when said shank and head are mounted in operative relation, a key insertable in said openings for locking said head on said shank, a bore extending longitudinally of said shank and communicating with the shank opening'into which the key is inserted, and a pin slidably mounted in said bore and movable into interengagement with said key, and means for releasably holding said pin in looking position.

10. In a rotary crusher, a hammer shank, a hammer head, a key engaging saidhead and said shank for detachably mounting said head on said shank, and a smooth locking pin slidable in a longitudinal bore in said shank into interengagement with said key for locking said head on said shank, and also slidable in said bore for releasing said key without removal of the pin.

' LESLIE G. EHMANN.

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

UNI'I'ED STATES PATENTS Number Name Date 848,273 Travis Mar. 26, 1907 1,170,370 Wald Feb. 1, 1916 1,618,826 Hiller Feb.,22, 1927 1,693,058 Shelton Nov. 27, 1928 2,170,407 Hartshorn Aug. 22, 1939 2,186,047 Stine Jan. 9, 1940 FOREIGN PATENTS Number Country Date 666,162 Germany Oct. 11, 1938 671,397 Germany Feb. 6, 1939 683,171 Germany Oct. 31, 1939