Disintegrator having grinding chamber with rotors including carrying disk with grinding wheels concentrically arranged thereon

A disintegrator comprises a housing (1) and a grinding chamber (2) accommodating grinding wheels mounted on shafts (9, 10) of electric motors. The peripheral zone of the chamber (2) accommodates inclined plates (13) of a classifier arranged about the circumference so that an annular slot (14) is formed between these plates and a cylindrical portion (3) of the chamber (2) through which the chamber (2) communicates with a separator (15). The separator (15) embraces one of the electric motors (11) and communicates by way of a passage (21) of return flow of air with an air distributor (22) embracing the electric motor (12). The distributor (22) is connected to the chamber (2) by way of annular slot (24) between the plates (13) of the classifier and the last grinding wheel (8) of the rotor. Connected to the separator (15) is a collector (18) of fine fraction of the material. The means for returning coarse fraction of the material has the form of an arcuate guide (29) arranged in close proximity to an opening (30) provided in the side wall (6) of the chamber (2) where through the chamber (2) communicates with the pipe (4) for charging the initial material (5).

FIELD OF THE INVENTION 
This invention relates to the art of comminuting materials, and more 
particularly to a disintegrator. 
BACKGROUND OF THE INVENTION 
There is known a disintegrator (USSR Inventor's Certificate No. 1,058,130) 
comprising a housing connected to a grinding chamber accommodating rotors 
with grinding wheels rotatable by electric motors. Provided between the 
rotor and housing is a separation zone wherethrough air is blown by means 
of pressure and suction blades. Connected to the housing is a pipe for 
evacuating finely ground material and air to a separator having the form 
of a cyclone with which a passage of return flow of air to the 
disintegrator communicates. The grinding chamber has an opening into the 
inlet pipe. 
The material is charged through the inlet pipe to the grinding chamber, 
where it is comminuted by the rotors. Fine fraction of the material is 
blown off to be conveyed through the pipe for evacuating the fine fraction 
to the separator, whereas coarse fraction is conveyed through the opening 
in the grinding chamber to the inlet pipe for regrinding. From the 
separator air is conveyed along the air flow return passage to the 
disintegrator. 
However, this prior art construction is bulky, and therefore takes much 
production space both horizontally and vertically. Another disadvantage is 
that much power is required for conveying material during operation of 
this disintegrator. 
There is also known a disintegrator (U.S. Pat. No. 4,093,127) comprising a 
housing having inlet and outlet pipes and accommodating a rotor-separator 
fashioned as a drum with inclined separating plates spaced from one 
another about the circumference of the peripheral zone of the drum. A 
passage for discharging finely ground material and air is provided at the 
outside of the drum. 
The material and air are conveyed from the inlet pipe to the 
rotor-separator. Rotation of the rotor causes the material to roll over, 
whereby lumps of the material are crushed and comminuted. Simultaneously, 
the rotor-separator is blown through by air. Particles having a size less 
than the clearance between the inclined separating plates are carried to 
the discharge passage and are evacuated through the outlet pipe. The 
material remains in the drum to complete comminution. 
However, this disintegrator suffers from low efficiency of grinding; in 
addition, the entire unit including the rotor-separator and air feeding 
system is excessively bulky. 
One more disintegrator is known (U.S. Pat. No. 2,656,988) comprising a 
housing with an inlet pipe accommodating a rotor with grinding blades and 
a rotor drive. The rotor is enclosed by a plurality of breaking and 
separating blades spaced from one another. The magnitude of clearance 
between the blades determines the boundary of material separation. The 
lower part of the housing accommodates collectors of coarse and finely 
ground materials with pipes for evacuating such materials, accordingly. 
The material delivered for comminution falls onto the grinding blades of 
the rotor to be thrown to the plurality of the inclined breaking blades. 
Particles having a size smaller than the clearance between the 
breaking-separating blades pass therebetween to enter the collector of 
fine fraction material, whereas the other particles are conveyed to the 
collector of coarse material. 
During operation the clearances between the blades tend to be clogged by 
the particles, whereby evacuation of the finely ground material becomes 
complicated. Also, because of only once-through comminution of the 
material the disintegrator is capable of producing relatively large-size 
particles as the end product. For reducing them further in size such 
large-size particles should be conveyed for repeated grinding to result in 
structural overcomplication of the disintegrator. The clearance between 
the blades needs also to be reduced thus again promoting clogging of the 
clearances and making the grinding process less efficient. 
There is finally known a disintegrator (International Application PCT/SU 
No. 84/0060) comprising a housing, a grinding chamber having a cylindrical 
portion with a pipe for charging the initial material to the grinding 
chamber, and two side walls. The grinding chamber accommodates rotors made 
up of carrying disks with grinding wheels mounted on shafts of electric 
motors. Communicating with the grinding chamber is a passage for 
evacuating the material from the grinding chamber to the classifier which 
includes a plurality of inclined plates and is connected by a passage for 
discharging finely ground material with a cyclone-type separator. 
Connected to the separator is a passage of return flow of air to the 
disintegrator, whereas connected to the classifier is a passage for 
returning coarse fraction of the material to regrinding. 
The material is carried with the air through the pipe to the grinding 
chamber where it is ground by the rotors and fed to the classifier in 
which the inclined plates act to separate fine fraction and convey it 
along the passage to the separator. Coarse fraction of the material flows 
from the classifier along the passage to the inlet pipe for regrinding. 
This prior art disintegrator suffers from low efficiency, since after 
grinding the entire material is mixed and conveyed with air to the 
classifier for the coarse and fine fractions to be separated. A 
substantial amount of power is consumed for classification and transport 
of the fine fraction and air to the separator, and conveying air from the 
separator back to the disintegrator. 
SUMMARY OF THE INVENTION 
This invention aims at providing such a disintegrator in which the 
arrangement of separate parts and units thereof would enable to simplify 
the disintegrator structurally, reduce it is size, and ensure consumption 
of a smaller amount of power for comminuting the material with the same 
efficiency. 
The aims of the invention are attained by that in a disintegrator 
comprising a housing, a grinding chamber having a cylindrical portion with 
a pipe for charging the initial material to the grinding chamber, and two 
side walls accommodating rotors including carrying disks with grinding 
wheels concentrically arranged thereon, the rotors being mounted on shafts 
of electric motors, a classifier with a plurality of inclined plates, a 
means for returning coarse fraction of the material to regrinding, a 
separator of air and fine fraction of the material with which communicates 
a passage of return flow of air and a collector of fine fraction of the 
material, according to the invention, the inclined plates of the 
classifier are arranged about the circumference in the peripheral zone of 
the grinding chamber at a distance from its cylindrical portion to form an 
annular slot facilitating communication of the separator of air and fine 
fraction of the material with the grinding chamber, the separator 
embracing one of the electric motors and communicating by way of the 
return flow air passage with an air distributor embracing the other 
electric motor and communicating with the grinding chamber by way of an 
annular slot formed by a clearance between the inclined plates of the 
classifier and the last grinding wheel, the means for returning coarse 
fraction of the material to regrinding having the form of an arcuate guide 
arranged in the immediate proximity to an opening made in the side wall of 
the grinding chamber and through which the grinding chamber communicates 
with the pipe for charging the initial material. 
In order to control fineness of the material being ground, it is advisable 
that the inclined plates of the classifier be pivotable. 
For increasing the production efficiency of the disintegrator, it is 
advisable to provide it with guide vanes arranged in the annular slot 
between the inclines plates of the classifier and cylindrical portion of 
the grinding chamber, and with a suction fan disposed in the separator of 
air and fine fraction of the material in the immediate proximity to this 
annular slot and connected to the carrying disk of one of the rotors. 
With the same aim in view, it is preferable that the disintegrator be 
provided with guide vanes arranged in the annular slot and formed by a 
clearance between the last grinding wheel and inclined plates of the 
classifier, and with a forced-draught fan arranged in the grinding chamber 
in the immediate proximity to this annular slot and connected to one of 
the rotors. 
The proposed construction of disintegrator makes it possible to 
substantially reduce its dimensions and bring down the amount of power 
required for its operation by 10-15%.

BEST MODE OF CARRYING OUT THE INVENTION 
The proposed disintegrator comprises a housing 1 (FIG. 1), a grinding 
chamber 2 having a cylindrical portion 3 with a pipe 4 for charging 
initial material 5 to the grinding chamber 2, and side walls 6. The 
grinding chamber 2 accommodates two rotors, each including carrying disks 
7 and grinding wheels 8 and mounted on shafts 9 and 10 of electric motors 
11 and 12, respectively. 
The disintegrator also comprises a classifier in the form of a plurality of 
inclined plates 13 (FIGS. 1 and 2) arranged about the circumference of the 
peripheral zone of the grinding chamber 2 at a certain distance from its 
cylindrical portion 3 to form an annular slot 14. Through the slot 14 the 
grinding chamber 2 communicates with a separator 15 of air and fine 
material fraction, which embraces the electric motor 11 and is disposed 
between the housing 1 and a cylinder 16. The annular slot 14 accommodates 
guide vanes 17 (FIGS. 1 and 2). The lower part of the separator 15 has 
connected thereto a collector 18 of fine fraction of the material, the 
bottom portion of which includes a unit for discharging the fine fraction 
of the material fashioned, for example, as a worm 19 with a drive 20. The 
separator 15 communicates by way of a passage 21 of return flow of air 
with an air distributor 22 which embraces the electric motor 12 and is 
disposed between the housing 1 and a cylinder 23. The distributor 22 
communicates with the grinding chamber 2 by way of an annular slot 24 
(FIGS. 1 and 2) defined by the clearance between the inclined plates 13 of 
the classifier and the last grinding wheel 8 provided with ventilation 
blades 25. The slot 24 accommodates guide vanes 26, whereas the grinding 
chamber accommodates a forced-draught fan 27 blades of which are disposed 
in immediate proximity to the slot 24 and which is connected to the 
carrying disk 7 of the rotor mounted on the shaft 10 of the electric motor 
12. Arranged inside the separator 15 is a suction fan 28 the blades of 
which are disposed in close proximity to the annular slot 14 and which is 
connected to the carrying disk 7 of the rotor mounted on the shaft 9 of 
the electric motor 11. The unit for returning large-size fraction of the 
material for regrinding is fashioned as an arcuate guide 29 secured in 
immediate proximity to an opening 30 provided in the side wall 6 of the 
grinding chamber 2 wherethrough it communicates with the pipe 4. 
In order to avoid penetration of large-size fraction of the material to the 
small-size fraction, an annular barrier 31 is provided between the fan 28 
and grinding chamber 2. For controlling fineness of the material the 
inclined plates 13 of the classifier are capable of swinging on hinges 32 
to thereby change the width of a clearance 33 between the plates 13. 
For opening the disintegrator the passage 21 (FIG. 3) is detachable having 
flanges 34, whereas the housing 1 of the disintegrator is provided with a 
hinge arrangement 35. A gate plate 36 is further provided for controlling 
the flow of air in the passage 21. 
A flow splitter 37 (FIG. 4) having the form of inclined plates is provided 
between the separator 15 and collector 18 of fine fraction of the 
material. 
The disintegrator according to the invention operates in the following 
manner. The initial material 5 (FIG. 1) is conveyed through the pipe 4 to 
the grinding chamber 2, passes through all the grinding wheels 8, and is 
conveyed further to the plurality of inclined plates 13 (FIG. 2) of the 
classifier. The comminuted material slides therealong, whereas uniformity 
of the flow is ensured by the ventilation blades 25. Simultaneously, the 
thus moving layer is blown through by a flow of air produced by the rotors 
of the disintegrator, fans 27, 28 (FIG. 1), and ventilation blades 25. 
Fine fraction of the material is evacuated through the clearances 33 (FIG. 
2) between the inclined plates 13 together with the air, this fine 
fraction entering the separator 15 (FIG. 1) through the annular slot 14. 
By virtue of circular movement of the flow produced by the guide vanes 17 
and fan 28, the material tends to settle on the walls of the separator 15, 
slides therealong, and enters the collector 18, wherefrom it is evacuated 
by the discharge means. Air from the separator 15 is conveyed along the 
passage 21 (FIG. 3) to the distributor 22 (FIG. 1) to enter the grinding 
chamber 2 through the annular slot 24. Large-size fraction of the material 
slides on the inclined plates 13 along the arcuate guide 29 to move 
through the opening 30 to the pipe 4 and enter the grinding chamber 2 for 
regrinding. 
Reduction in the amount of power to be consumed during comminution is 
attained by the following. First, through accommodating the classifier in 
the grinding chamber 2 embracing the rotors; in this zone the density of 
the mixture is low, and therefore grading the material to size takes place 
without expending the energy for feeding the material to the classifier. 
Second, through immediately connecting the separator 15 with the grinding 
chamber 2 resulting in reduced amount of power consumed for conveying the 
material. And finally, through reducing the travel path of air. 
In addition, this construction of the disintegrator is sufficiently 
small-size to occupy less production floor area horizontally and 
vertically. 
INDUSTRIAL APPLICABILITY 
The invention can be utilized with success for comminuting construction 
material, in the chemical technology, and for milling grain, particularly 
for producing alcohol.