US1946763A - Rock-crushing machine - Google Patents

Rock-crushing machine Download PDF

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US1946763A
US1946763A US541796A US54179631A US1946763A US 1946763 A US1946763 A US 1946763A US 541796 A US541796 A US 541796A US 54179631 A US54179631 A US 54179631A US 1946763 A US1946763 A US 1946763A
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head
machine
crushing
breaker
plates
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US541796A
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William H Sallwasser
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B02CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02CCRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C1/00Crushing or disintegrating by reciprocating members
    • B02C1/02Jaw crushers or pulverisers
    • B02C1/08Jaw crushers or pulverisers with jaws coacting with rotating roller

Definitions

  • breaking plates which may be adjusted toward and from the crushing head without employing holding means of a character that will permit of lost motion and consequent increase in the distance between the breaker plates and the crushing head.
  • a further object of the present invention is to produce a crushing machine in which the breaker plates are reversible so that, after wear has taken place along one half thereof, they may be turnedend for end and present new working faces or surfaces, thereby doubling the life thereof.
  • Another object of the present invention is to provide simple, easily replaceable safety means that will break down or fail under abnormal stresses before any of the other parts of the machine fail, thereby protecting the machine against material damage in case a piece of tramp iron, for example, should be fed into the same.
  • I employ a horizontal eccentric shaft surrounded by a cylindrical crushing head that is rotatable thereon; associating with the head two curved breaker plates, one on each side. These breaker plates are so shaped and positioned that the crushing forces exerted by the head are substantially normal to the surfaces of the plates throughout the entire working zones. --Since the head is rotatable on the shaft, its crushing movements are simply movements toward the breaker plates and not rotary movements, whereby abrading action is avoided.
  • a crushing head of this type is very heavy and, when the machine is empty, even though the head be supported on antifriction bearings, it will tend to turn with the shaft.
  • the head may acquire a high rotary speed before a charge is dumped into the machine. Then, when the head engages with the rock, which is also in contact with the breaker plate toward which the head is moving, the turning movement of the head is rapidly checked and, in fact, there may be an abrupt stoppage of all rotary movement of the head; the result being that the machine as a whole is subjected to enormous stresses that tend to disrupt it.
  • One of the objects of the present invention is to guard against the condition just described, by preventing the head from acquiring momentum through tu ing with the shaft, while permitting the necessary turning movements to permit different parts of the surface of the cylinder to be brought into the working zone or zones and thus distribute the wear over the entire periphery of the cylinder.
  • a further object of the present invention is .to produce a simple and novel crushing machine of compact form wherein the main frame or housing is of a peculiar shape to afford maximum strength and rigidity.
  • Figure 1 is a combined end view and transverse section of a machine embodying the present invention
  • Fig. 2 is a central longitudinal section through one end of the machine
  • Fig. 3 is a side view of the machine, on a smaller scale
  • 35 Fig. 4 is a transverse section through the lower part of the machine, showing a modification.
  • 1 represents a horizontal shaft having a central portion 2 that is slightly eccentric.
  • the shaft extends through and is journalled in the ends of a heavy, rugged frame in the form of a casing or housing 3.
  • a crushing head Surrounding the shaft and rotatable thereon is a crushing head comprising a heavy sleeve 4 enclosed in detachable wearing plates 5.
  • the side walls 6, 6 of the frame or housing curve inwardly toward the top, approaching'each other only near enough to provide a mouth or-opening '7 in the top of the frame.
  • Between the wall 6 and the crushing head are two breaker plates 8, 8, each in the form of a segment of a cylinder larger in diameter than the head.
  • each breaker plate has on vthe rear or outer side two semi-cylindrical grooves 9 and 10, paralleling and near the long In the upper groove 9 is set the lower edge of a safety plate 11 bolted or otherwise detachably connected to the corresponding frame member 6; the edge 12 of the plate that fits the cylindrical seat being in the form of a segment of a cylinder so as to form a rocking joint between the breaker plate and the safety plate.
  • the seat in the breaker plate is held against the edge of the safety plate by means of bolts 13 extending through the frame member 6 and each having a laterally projecting part 14 engaged with a hook 15 on the breaker plate.
  • a second safety plate is fitted at one edge into In the arrangesafety plate 16 are rounded, as indicated at 17 and 18.
  • the edge 17 fits into the seat 10 and the edge 18 fits into a similar seat 19 in the frame.
  • Bolts 20, similar to the bolts 13, and engazed with hooks 21 on the breaker plate, pass through the frame member 6 and serve to draw the breaker plate firmly against the safety plate 16 and the latter firmly against the seat 19. It is desirable that the breaker plates be adjustable to permit the degree of coarseness or fineness of the product of the machine to be varied. In the arrangement shown in Fig.
  • such adjustment may be secured by placing the outer end of the safety plate 16 either in the seat 19 or in any one of a plurality of additional seats so located thatthe space between the lower end of the breaker plate. and the head will be different for each of the various positions which the safety plate may take.
  • the breaker plates are made reversible, the seats 9 and 10 and the hooks 15 and 21 being symmetrically disposed with respect to a radial plane pressing through the plates halfway between the seats. Therefore, after the lower halves of the plates have become worn, the plates may be detached and turned upside down, presenting new wearing faces and thus doubling the lives of the plates.
  • the breaker head must not be permitted to turn with the shaft when the machine is empty until it acquires considerable momentum. If a charge of rock were suddenly dumped into the machine with the breaker head rotating rapidly, the turning movement of the head would be suddenly checked as soon as the head began to press the rock against one of the breaker plates; and the stresses resulting from the abrupt stopping or deceleration of the heavy head would seriously strain the machine and perhaps destroy the same. This is particularly true in the case of a high speed machine. I have, therefore, provided means to prevent rotation of the crushing head in a manner that will, or might, be injurious to the machine. In the arrangement shown in Fig.
  • the other modified feature relates to the controlling of the rotary movements of the cylindrical crushing head. Instead of the brake shoe, I employ a number of pins, indicated at 35, that may be set into sockets 36 distributed around the periphery of the head.
  • pins project far enough so that, when one or more are placed in openings on the under side of the cylinder, the pin or pins will engage with the lower ends of the breaker plates and stop further movement of the head, if it should begin to revolve in either direction.
  • This particular arrangement will prevent the head from automatically creeping, so as constantly to present new superficial wearing areas; but, upon removing the pin or pins, the head may be turned to any desired angle so as to present wearing surfaces that will remain in service until the head is again shifted.
  • a rotatable eccentric member a cylindrical crushing head surrounding said member and having a bearing thereon to permit relative rotary movements, a stationary breaker plate beside the head and having a concave face directed to the latter, the parts being so proportioned that there is a space between the head and the breaker plate narrowing gradually from one end to the other, and brake means engaging the head to prevent free rotary movement of said head.
  • a rotatable eccentric member In a crushing machine, a rotatable eccentric member, a cylindrical crushing head surrounding said member and having a bearing thereon to permit relative rotary movements, stationary breaker plates one on each side of the head, and brake means eng in the head to prevent free rotary movement of said head.
  • a rotatable eccentric member In a crushing machine, a rotatable eccentric member, a crushing head surrounding said member and having a bearing thereon to permit relative rotary movements, a brake shoe, and means pressing said shoe against said head, and a breaker plate beside and spaced apart from said head.
  • a movable crushing head In a crushing machine, a movable crushing head, a stationary frame member, a breaker plate between said head and said frame member, similar bearing seats at opposite ends of said breaker plate on the side toward the said frame member, elements extending from said frame member and fitting into either of said seats.
  • said breaker plate being reversible so that it may be turned end for end as wear occurs said elements being mounted in the frame member whereby they fit into the seats in either position of the plate, and means extending between said plate and said frame member to draw said seats into intimate engagement with the aforesaid elements.
  • a movable crushing head In a crushing machine, a movable crushing head, a stationary frame member, a breaker plate between the head and the said frame member, engaging parts on one end of said plate and on the frame member constituting a hinge Joint to permit the breaker plate to be swung toward and from said head, a strut engaged at one end with the other end of the breaker plate and extending toward the frame member, means on the frame member abutting against the adjacent end of the strut to cause the breaker plate to stand in any one of a plurality of angular positions with respect to its hinge axis, and means to draw the breaker plate and the frame member together and into intimate contact with the ends of the strut.
  • a movable crushing head In a crushing machine, a movable crushing head, a stationary frame member, a breaker plate between the head and the said frame member, engaging parts on one end of said plate and on the frame member constituting a hinge joint to permit the breaker plate to be swung toward and from said head, a strut engaged at one end with the other end of the breaker plate and extending toward the frame member, said frame member having a plurality of seats to receive the other end of the strut to permit the strut to hold the said plate in any one of a plurality of angular positions, and means to draw the plate and the frame member into intimate contact with the strut.

Description

Feb. 13, 1934. w s w ss 1,946,763
ROCK CRUSHING MACHINE Filed June 3, 1931 2 Sheets-Sheet 1 Feb. 13, 1934. w. H. SALLWASSER ROCK CRUSHING MACHINE Filed June 3, 1931 2 Sheets-Sheet 2 Patented Feb. 13, 1934 UNITED STATES PATENT OFFICE r 6 Claims.
produce a crushing machine of simple and novel construction, having breaking plates which may be adjusted toward and from the crushing head without employing holding means of a character that will permit of lost motion and consequent increase in the distance between the breaker plates and the crushing head.
A further object of the present invention is to produce a crushing machine in which the breaker plates are reversible so that, after wear has taken place along one half thereof, they may be turnedend for end and present new working faces or surfaces, thereby doubling the life thereof.
Another object of the present invention is to provide simple, easily replaceable safety means that will break down or fail under abnormal stresses before any of the other parts of the machine fail, thereby protecting the machine against material damage in case a piece of tramp iron, for example, should be fed into the same.
In carrying out my invention, I employ a horizontal eccentric shaft surrounded by a cylindrical crushing head that is rotatable thereon; associating with the head two curved breaker plates, one on each side. These breaker plates are so shaped and positioned that the crushing forces exerted by the head are substantially normal to the surfaces of the plates throughout the entire working zones. --Since the head is rotatable on the shaft, its crushing movements are simply movements toward the breaker plates and not rotary movements, whereby abrading action is avoided. A crushing head of this type is very heavy and, when the machine is empty, even though the head be supported on antifriction bearings, it will tend to turn with the shaft. Therefore, in a high speed machine, starting from a position of rest, and empty, the head may acquire a high rotary speed before a charge is dumped into the machine. Then, when the head engages with the rock, which is also in contact with the breaker plate toward which the head is moving, the turning movement of the head is rapidly checked and, in fact, there may be an abrupt stoppage of all rotary movement of the head; the result being that the machine as a whole is subjected to enormous stresses that tend to disrupt it. One of the objects of the present invention is to guard against the condition just described, by preventing the head from acquiring momentum through tu ing with the shaft, while permitting the necessary turning movements to permit different parts of the surface of the cylinder to be brought into the working zone or zones and thus distribute the wear over the entire periphery of the cylinder.
A further object of the present invention is .to produce a simple and novel crushing machine of compact form wherein the main frame or housing is of a peculiar shape to afford maximum strength and rigidity.
The various features of novelty whereby my invention is characterized will hereinafter be pointed out with particularity in the claims; but, for a full understanding of my invention and of its objects and advantages, reference may be had to the following detailed description taken in connection with the accompanying drawings, wherein:
Figure 1 is a combined end view and transverse section of a machine embodying the present invention; Fig. 2 is a central longitudinal section through one end of the machine; Fig. 3 is a side view of the machine, on a smaller scale; and 35 Fig. 4 is a transverse section through the lower part of the machine, showing a modification.
Referring to the drawings, 1 represents a horizontal shaft having a central portion 2 that is slightly eccentric. The shaft extends through and is journalled in the ends of a heavy, rugged frame in the form of a casing or housing 3. Surrounding the shaft and rotatable thereon is a crushing head comprising a heavy sleeve 4 enclosed in detachable wearing plates 5. The side walls 6, 6 of the frame or housing curve inwardly toward the top, approaching'each other only near enough to provide a mouth or-opening '7 in the top of the frame. Between the wall 6 and the crushing head are two breaker plates 8, 8, each in the form of a segment of a cylinder larger in diameter than the head. These plates are so placed that their lower ends are near the crushing head, at a considerable distance below the horizontal plane containing the long axis of the shaft, whereas the upper ends are disposed at a considerable distance above the head and spaced a considerable distance apart therefrom; thereby forming two passages or chutes leading downwardly from the mouth or inlet 7 in the no edges.
frame, on opposite sides of the crushing head, and gradually decreasing in width from the top toward the bottom.
When the shaft revolves, its eccentricity will cause the head to move up and down and from side to side; so that, the machine be filled with rock, the head will exert a crushing pressure first in the direction of one breaker plate and then in the direction of the other. The parts are so proportioned that the crushing stresses are at all times substantially normal to the surfaces of the breaker plates against which the rock is pressed, thereby preventing slippage of the rock in the machine and avoiding wear through abrasion.
The breaker plates are so mounted that they will be rigidly supported and so that no lost motion can develop to increase the effective spacing between the head and the plates. Means .are also provided to protect the parts of the machine through the employment of simple safety .devices which will fail under abnormal loads and which may easily be replaced. In the arrangement shown, each breaker plate has on vthe rear or outer side two semi-cylindrical grooves 9 and 10, paralleling and near the long In the upper groove 9 is set the lower edge of a safety plate 11 bolted or otherwise detachably connected to the corresponding frame member 6; the edge 12 of the plate that fits the cylindrical seat being in the form of a segment of a cylinder so as to form a rocking joint between the breaker plate and the safety plate. The seat in the breaker plate is held against the edge of the safety plate by means of bolts 13 extending through the frame member 6 and each having a laterally projecting part 14 engaged with a hook 15 on the breaker plate.
A second safety plate is fitted at one edge into In the arrangesafety plate 16 are rounded, as indicated at 17 and 18. The edge 17 fits into the seat 10 and the edge 18 fits into a similar seat 19 in the frame. Bolts 20, similar to the bolts 13, and engazed with hooks 21 on the breaker plate, pass through the frame member 6 and serve to draw the breaker plate firmly against the safety plate 16 and the latter firmly against the seat 19. It is desirable that the breaker plates be adjustable to permit the degree of coarseness or fineness of the product of the machine to be varied. In the arrangement shown in Fig. 1, such adjustment may be secured by placing the outer end of the safety plate 16 either in the seat 19 or in any one of a plurality of additional seats so located thatthe space between the lower end of the breaker plate. and the head will be different for each of the various positions which the safety plate may take. In the arrangement shown, there are two additional stationary seats,
indicated at 22 and 23.
It will-be seen that, after the parts of the machine have been assembled, the breaker plate bears against solid abutments and cannot move away from the crushing head without destroying the abutments; thereby avoiding the lost 7o. motion whichinevitably occurs when the crushing load must be borne by screw threads. In the event that a piece of tramp iron, for example, should get into the machine, the corresponding breaker plate would yield through 'failure of the safety plate 11, or of the safety plate 16, which acts as a strut between the frame and the breaker plate, or the failure of both of these plates, so that no other part of the machine would be injured. It is a matter of only a few moments to insert one or two new safety plates, and, therefore, the entrance into the machine of anobject that will ordinarily seriously damage a crushing machine will have no more effect than to place it out of operation for a very short interval of time.
The breaker plates are made reversible, the seats 9 and 10 and the hooks 15 and 21 being symmetrically disposed with respect to a radial plane pressing through the plates halfway between the seats. Therefore, after the lower halves of the plates have become worn, the plates may be detached and turned upside down, presenting new wearing faces and thus doubling the lives of the plates.
The breaker head must not be permitted to turn with the shaft when the machine is empty until it acquires considerable momentum. If a charge of rock were suddenly dumped into the machine with the breaker head rotating rapidly, the turning movement of the head would be suddenly checked as soon as the head began to press the rock against one of the breaker plates; and the stresses resulting from the abrupt stopping or deceleration of the heavy head would seriously strain the machine and perhaps destroy the same. This is particularly true in the case of a high speed machine. I have, therefore, provided means to prevent rotation of the crushing head in a manner that will, or might, be injurious to the machine. In the arrangement shown in Fig. 1, this is accomplished by causing a brake shoe 25 to bear on the under side of the crushing head; this shoe being held in frictional engagement with the head by means of a long leaf spring 26 spanning the space between the two side walls of the frame. -This shoe will offer sufficient resistance to rotation of the head that the latter will remain stationary when the shaft starts to turn while the machine is empty. However, the cylinder may turn about its long axis and, particularly, the cylinder may creep, so as from time to time to present new wearing surfaces and thus distribute the wear over the entire periphreral surface of the cylinder.
-In Fig. 4, I have illustrated some slight modifications. The safety plates 30, corresponding to the plates 16 in the other form, engage seats 31 in blocks 32 resting on shelves or platforms 33 on the side members of the frame. Adjustments are secured by inserting thin plates or shims 34 behind the blocks, thereby preserving the rigidity of the abutments for the safety plates and, at the same time, affording quick and easy adjustment. The other modified feature relates to the controlling of the rotary movements of the cylindrical crushing head. Instead of the brake shoe, I employ a number of pins, indicated at 35, that may be set into sockets 36 distributed around the periphery of the head. These pins project far enough so that, when one or more are placed in openings on the under side of the cylinder, the pin or pins will engage with the lower ends of the breaker plates and stop further movement of the head, if it should begin to revolve in either direction. This particular arrangement will prevent the head from automatically creeping, so as constantly to present new superficial wearing areas; but, upon removing the pin or pins, the head may be turned to any desired angle so as to present wearing surfaces that will remain in service until the head is again shifted.
It should be noted that inward curvature of the sides 6 of the main frame. toward the top, produces the effect of diagonal bracing, giving great strength and rigidity to the frame.
While I have illustrated and described with particularity only a single preferred form of my invention, with a few slight modifications, I do not desire to be limited to the exact structural details thus illustrated and described; but intend to coverl all forms and arrangements which come within the definitions of my invention constituting the appended claims.
I claim:
1. In a crushing machine, a rotatable eccentric member, a cylindrical crushing head surrounding said member and having a bearing thereon to permit relative rotary movements, a stationary breaker plate beside the head and having a concave face directed to the latter, the parts being so proportioned that there is a space between the head and the breaker plate narrowing gradually from one end to the other, and brake means engaging the head to prevent free rotary movement of said head.
2. In a crushing machine, a rotatable eccentric member, a cylindrical crushing head surrounding said member and having a bearing thereon to permit relative rotary movements, stationary breaker plates one on each side of the head, and brake means eng in the head to prevent free rotary movement of said head.
3. In a crushing machine, a rotatable eccentric member, a crushing head surrounding said member and having a bearing thereon to permit relative rotary movements, a brake shoe, and means pressing said shoe against said head, and a breaker plate beside and spaced apart from said head.
4. In a crushing machine, a movable crushing head, a stationary frame member, a breaker plate between said head and said frame member, similar bearing seats at opposite ends of said breaker plate on the side toward the said frame member, elements extending from said frame member and fitting into either of said seats. said breaker plate being reversible so that it may be turned end for end as wear occurs said elements being mounted in the frame member whereby they fit into the seats in either position of the plate, and means extending between said plate and said frame member to draw said seats into intimate engagement with the aforesaid elements.
5. In a crushing machine, a movable crushing head, a stationary frame member, a breaker plate between the head and the said frame member, engaging parts on one end of said plate and on the frame member constituting a hinge Joint to permit the breaker plate to be swung toward and from said head, a strut engaged at one end with the other end of the breaker plate and extending toward the frame member, means on the frame member abutting against the adjacent end of the strut to cause the breaker plate to stand in any one of a plurality of angular positions with respect to its hinge axis, and means to draw the breaker plate and the frame member together and into intimate contact with the ends of the strut.
6. In a crushing machine, a movable crushing head, a stationary frame member, a breaker plate between the head and the said frame member, engaging parts on one end of said plate and on the frame member constituting a hinge joint to permit the breaker plate to be swung toward and from said head, a strut engaged at one end with the other end of the breaker plate and extending toward the frame member, said frame member having a plurality of seats to receive the other end of the strut to permit the strut to hold the said plate in any one of a plurality of angular positions, and means to draw the plate and the frame member into intimate contact with the strut.
wnmam H. BALLWASSER.
US541796A 1931-06-03 1931-06-03 Rock-crushing machine Expired - Lifetime US1946763A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2464732A (en) * 1945-05-01 1949-03-15 Jr Samuel W Traylor Jaw crusher
US3150838A (en) * 1958-04-04 1964-09-29 Adams Engineering Company Impact crusher
US3514045A (en) * 1967-09-11 1970-05-26 Dravo Corp Apparatus for converting pea gravel into useful aggregate
US3638870A (en) * 1969-12-16 1972-02-01 David Bourne Rock-crushing machine
US4165042A (en) * 1978-04-12 1979-08-21 The United States Of America As Represented By The Secretary Of The Interior Rotary jaw crusher
US5482218A (en) * 1993-10-20 1996-01-09 Ha; Yonggan Rock crushing apparatus and method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2464732A (en) * 1945-05-01 1949-03-15 Jr Samuel W Traylor Jaw crusher
US3150838A (en) * 1958-04-04 1964-09-29 Adams Engineering Company Impact crusher
US3514045A (en) * 1967-09-11 1970-05-26 Dravo Corp Apparatus for converting pea gravel into useful aggregate
US3638870A (en) * 1969-12-16 1972-02-01 David Bourne Rock-crushing machine
US4165042A (en) * 1978-04-12 1979-08-21 The United States Of America As Represented By The Secretary Of The Interior Rotary jaw crusher
US5482218A (en) * 1993-10-20 1996-01-09 Ha; Yonggan Rock crushing apparatus and method

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