US2521591A - Apparatus for converting crushed material - Google Patents

Description

Sept. 5, 1950 w. s. MARTIN APPARATUS FOR CONVERTING cRUsHED MATERIAL 2 Sheets-Sheet 1 Filed June l, 1945 IN V EN TOR.

Sept 5, 1950 w. s. MARTIN 2,521,591

APPARATUS FOR CONVERTING CRUSHED MATERIAL /1 111/ /fffnfn/ff/q,

l@ 54 @P3/w@ H/ 1 fr 32d IN VEN TOR.

` furnace.

Patented Sept. 5, 1950 UNITED sTATEs PATENT oFFlcE APPARATUS FOR CONVERTING cRUsHED MATERIAL Warren S. Martin, Massapequa, N. Y.

Application June 1, 1945, Serial No. 597,126 7 claims. (c1. 26a- 21) This invention relates to apparatus for converting crushed mineral material. More particularly, this invention relates to apparatus for continuous heat treatment of crushed material.

An important object of the invention is to provide a furnace with a vibratory deck or hearth serving as the bottom of the furnace, gas seals at the ends and sides of said deck and means beneath said deck for vibrating said deck.

According to one embodiment of the invention heat is applied directly to a material bed on the deck. According to another embodiment of the invention, the' heat may be applied to the upper surface of a 4muifle of suitable material such as V`carbo'rundu'm and may be transmitted therethrough to gaseous material passingover the vivbratory deck. Such gaseous material may be adapted to reduce material on said hearth.

Other objects, features and advantages will appear upon consideration of the following detailed description and of the drawings in which Fig. 1 is a somewhat diagrammatic longitudinal vertical section of a furnace constituting one embodiment of the invention;

Fig. 2 is a View showing on a larger scale the ends of the furnace of Fig. '1, the central part being broken away;

Fig. 3 is a section taken along the line 3-3 of Fig. 2;

Fig. 4 is a longitudinal vertical section, similar to Fig. 2, of a modification; and

Fig. 5 is a vertical section taken along the line 5-5 of Fig. 4.

In Fgsl, 2 and 3, there is illustrated a preferred embodiment of the furnace of the present invention. The foundation of any suitable material such as concrete comprises side walls I and a wall II at the discharge end of the dation walls I0 and Il are side walls I2 and a discharge end wall I3 of the furnace proper, these walls being constructed of suitable refractory material. At its top the furnace may have 'a fiat roof I4 made up of members'or blocks of refractory material suspended from I-beams supported at their ends on the side walls I2.

Extending across between the side walls I2 and substantially from end to end of the furnace is a vibratory deck or hearth I which serves as 4the bottom of the furnace proper and also as part of a vibrating feeder or conveyer. The material is opened up by this vibrating movement and the heat treatment is accelerated.

'The hearth I5 comprises a box I 6 carried by Supported respectively by said foun-r a suitable frame including longitudinal members I1 and transverse members I8. Said' box which is illustrated on Fig. 3 as having high sides, may be filled to an intermediate level with a body I9 comprising heat insulating and refractory material having metal reinforcements (Fig. 3). This body I9 of refractory material is formed with side walls 20 to keep the material from escaping at the sides and these side walls and the side edges of the box I6 extend beneath overhanging portions of theside walls I2. Beneaththe hearth or deck there is a gas seal extending completely around the periphery of the hearth. This seal may be of the lute type. In some cases it may be desired to use irebrick in constructing the body I9, in view of the abrasion-resisting quality of the brick.

Preferably the hearth I5 has a generally downward inclination from its inlet end to its outlet end near wall I3, and the upper surface of the refractory body I9 isformed with a plurality of successive steps so that the material is fed from step to step and is thoroughly turned over and opened. I

As illustrated the material is supplied to the furnace through a feeder 2l, and a chute 22 receiving material from the feeder-and extending at its lower end over a lip 23 inclined outwardly from the upper edge of the adjacent end wall vof the box I6. The lower end of said chuteis secured to the top or roof of the furnace and is Vspaced from said lip 23 to prevent striking of the terial into the furnace may be controlled by a sliding gate 24 extending through the top of the flirnace,` and in this way material may be accumulated to assure sealing of the apparatus at this point.

At its discharge end the vibratory hearth I5 'isprovided with a lip 25 overlying a lip 26 lori-the I*casing of a discharge device 2l having a rotary `ribbed member `28 mounted in a part cylindrical chamber and discharging into an outlet 29; `If

maybe sealed Aby the treated material without desired thejlip 25 may be' cooled in anysuitable `man-1'11er.` l

They furnace chamber may be heated by means of :burners 30 projecting inwardly through the upper parts of the side walls I2 near the discharge end of the furnace and extending as far toward the inlet end as desired.

The hot gases from the burning of fuel in the burners and also those produced by the treatment of the material may pass to the inlet end of the furnace and be discharged from the furnace through a flue 3l connected to the top of the furnace. In this travel of the hot gases overthe material bed, there is a decidedv temperature drop indicating eiiicient utilization of the heat.

The hearth or deck I5 may be supported by inclined compression springs 32 interposed between the longitudinal members I1 and supports 33 which may be projecting portions of the side walls I0 of the foundation. The vibratory movement of the hearth may be effected by suitable vibrators 34, here illustrated as hydraulic vibrators comprising in each case a cylinder 35 having its base 36 connected by a pivot 31 to a bracket 38 on a fixed support 39 and a ram comprising a piston 40 in said cylinder and a piston rod 4I connected to said piston and to a pivot 42 in a bracket 43 projecting downwardly from said vibratory hearth or deck. At the free end of the cylinder, the piston rod 4I passes through the head 44 of the cylinder.

Fluid such as oil is admitted under pressure, through a duct 45 into the space between the cylinder base and the piston, long enough to move the piston outwardly the requisite distance and is then shut off. The oil is discharged through a duct 46 having a central entrance in said base 36, into an exhaust duct 41, when the piston is forced back in the return movement of the hearth. This return movement ma'y be cushioned by means of a tapered plug 46 on the side of the piston opposite the piston rod and arranged to enter said central entrance of duct 46, where although it is too small in cross section to close said central entrance, it will progressively restrict the fiow of fluid and cushion the return movement. It will be understood that a valve arrangement of known form may be utilized to .openand close the connection between the duct 45 and the source of its supply and correspondingly close and open a connection between pasvsage 46, duct 41 and a discharge line. The return movements may be assisted or produced by supplying fluid such as oil between the piston 40 and the head 44 through a duct 49 in the latter. This action may be effected by producing and relieving pressure in this part of the ycylinder or by applying pressure from yielding means, such as spring means.

The refractory body I9 of the deck or bed I5 may be reinforced. As indicated in Fig. 3, this may be done, by providing metal reinforcing material 50 substantially parallel to the upper surface of the deck and transversely extending reinforcing material 5I attached to devices 52 in the side walls of the box I6 and carried downwardly and upwardly across the bed, being fastened at the low `points to devices 53 secured to the bottom of the box and at the high points to the material 50.

It will be evident that the deck or hearth I5 is protected against contact with hot gases of combustion by the material thereon and that the discharge device 21 may be protected by the treated material by maintaining an accumulation of treated material thereover.

In Figs. 4 and 5, there is disclosed a modification which differs from the iirst form ofv furnace principally by providing a muiile 54 of suitabley material such as carborundum extending across the furnace below the burners, 30a, an inlet 55 in the wall I 3a through which suitable gases, CO for example, may be introduced beneath the muilie to assist in obtaining the desired result. In this form the material is heated by indirect or radiant heat.

The walls I2a receive the edges of the muIIle 54 which may be arched, and in orderto prevent spreading of these walls under lateral stresses thus produced, they may be supported by suitable means which may include l? beams 56, engaging said walls at their outer faces.

Due to the use of the muflie 54, there are separate means for discharging gases from the two chambers separated by the muiile. In arranging for such separate discharge means, an arch-supported wall 51 may be provided to close the right hand end (Fig. 4) of the chamber 53 above the muie. The chamber 59 below the munie extends beneath the Wall 51 to provide for a flue or stack 3 Iathrcugh which gases from the lower chamber 5B are discharged, and for a chute 22a, through which material to be treated is fed into said lowervchamber 59 and deposited on the vibrating hearth or deck I5a. At the left of wall 51 is an upright flue or stack 60 through which gases from the upper chamber 58 are discharged.

The hearth 'or deck l5a is supported in the same general way as the deck of the rst form. by springs 32a interposed between deck frame members I1a and supports 33a. Vibration of the deck I5a may be effected in any suitable manner, for example by standard vibrators 34a connected to the frame of said deck or hearth I5a and yieldingly supported by struts 6I mounted on springs 62 carried by parts of the foundation.

At its inlet end the deck I5a is provided with a lip 23a. beneath said chute 22a and spaced therefrom to avoid striking, the apparatus being sealed at this point by a suitable accumulation of material at this location under control of a vertically slidable gate 24a.

At its discharge end the deck I5a is provided with a lip 25a overlying a lip 26a. of a discharge device 21a in which the discharge is controlled by slidable gates 28a operated alternately by hand or by a suitable operating device. It should be noted Ythat in the form of apparatus illustrated in Fig. 4, the hearth I5a is substantially horizontal and the muie 54 is similarly arranged.

Although the hearth I5 of the first form of the apparatus has been described generally as having one end higher than the other and as having steps at its upper surface, there has been no description of various features which appear to be of importance and which will now be considered. y

The upper surface of said deck I5 slopes downwardly from its receiving end to an intermediate point and then extends substantially horizontally to its discharge end. In the sloping or inclined portion of thel hearth I5 there are broad steps 63 with generally flat tops and in the horizontal part there are lnarrow steps 64 of which the tops slope downwardly and rearwardly. The forward edges of steps 64 are substantially in the same horizontal plane and between these forward edges are pockets 65 located at the In passing along the steps in the horizontal part of the hearth I5, the larger and heavier objects or particles sink into the pockets 65 and are held back with reference to the lighter particles so as to receive additional treatment and be broken down. By having the burners 39 close to the material bed as in the first form, the heat from the burner flames passes largely by radiation directly to the material bed and is absorbed thereby. ln the second form of furnace, the burners are close to the muffle 54 and the greater part of the heat from the adjacent burners 50a passes by direct radiation tol the munie and from the other side of the mule the heat passes by radiation to the material bed.

It should be understood that the positions of the discharge lues and the burners may be varied to control the heating in different parts of the furnace.

It should be understood that various changes may be made and that certain features may be used without others, without departingfrom the true scope and spirit of the invention.

Having thus described my invention, I claim:

1. A high temperature heat treatment furnace comprising a chamber lined with refractory material and having as its bottom a vibratory re fractcry deck eiective to feed therealong a bed of crushed mineral material and the like, means for vibrating said deck positioned beneath said deck, gas seal means at the side edges of said deck, gas seal means for introducing such inaterial into the chamber and depositing it on the receiving end of said deck, gas seal means for receiving material rozn the discharge end of said deck and discharging it from the furnace, a gas outlet above said receiving end, and heating means for the material on said deck including burners in said chamber and spaced from said outlet.

2. A furnace comprising a chamber lined with refractory material having as its bottom a refractory vibratory hearth having a downwardly inclined portion at its receiving end and then a flat portion inclined upwardly from the plane of said inclined portion.

3. The combination according to claim 2 wherein said downwardly inclined portion has steps with wide substantially horizontal tops.

4. The combination according to claim 2 wherein said flat portion is provided with steps inclined rearwardly to form pockets to the front of said steps to receive and retain for additional treatment the larger and heavier bodies.

5. A high temperature heat treatment furnace comprising a chamber lined with refractory material and having as its bottom a vibratory deck eiective to feed therealong a bed of crushed mineral material, means for vibrating said deck beneath said deck, said deck having an upper face of refractory material, gas seals between said Vibratory deck and the side Walls of said chamber, gas seal means for introducing such material into the chamber and depositing it on the receiving end of said deck, gas seal means for receiving material from the discharge end of said deck and discharging it from the furnace, means for subjecting the material at the discharge end of said deck to high temperatures, and means for discharging resulting high temperature gases from the receiving end of said furnace.

6. A high temperature furnace as set forth in claim 1 wherein said vibratory deck is provided with a plurality of steps to cause the material to roll over as it passes from step to step toward the discharge end of the deck.

7. A high temperature furnace as set forth in claim 1 wherein there is a muille beneath said burners and over said vibratory deck to radiate heat thereto, a liuc to draw gases from the part of the chamber above said mutlle, and a flue to draw gases from the part of the chamber below said muflie.

WARREN S. MARTIN.

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

UNITED STATES PATENTS Name Date Evertson Nov. 27, 1866 Cullen May 27, 1884 Wentz Apr. 9, 1907 Horn Aug. 3, 1909 Williey Nov. 9, 1909 Dwight et al Nov. 5, 1918 Hyde Oct. 23, 1928 Schulenberg Nov. 6, 1928 Gillette Nov. 5, 1935 Betterton et al May 26, 1936 Betterton et al. May 26, 1936 Lindner May 26, 1936 Clauss et al Dec. 28, 1937 Ahlmann Sept. 26, 1939 Brassert et al Apr. 13, 1943 Somes Mar. 7, 1944 Number

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