CA1141726A - Screen for vibrating centrifugal separation machines - Google Patents
Screen for vibrating centrifugal separation machinesInfo
- Publication number
- CA1141726A CA1141726A CA000330995A CA330995A CA1141726A CA 1141726 A CA1141726 A CA 1141726A CA 000330995 A CA000330995 A CA 000330995A CA 330995 A CA330995 A CA 330995A CA 1141726 A CA1141726 A CA 1141726A
- Authority
- CA
- Canada
- Prior art keywords
- screen
- height
- pitch
- layer
- sifting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Combined Means For Separation Of Solids (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A screen for vibrating centrifugal separation machines, which screen is in the form of a solid of revolution and comprises a sifting part and a non-sifting part. The genera-trix of the sifting part has a stepped shape, each step forming a solid of revolution in the form of a hollow conical frustum whose major base faces opposite to the movement of the layer of the loose material under treatment. This con-struction substantially increases the separating properties of the screen in using it in various vibrating centrifugal separation machines.
A screen for vibrating centrifugal separation machines, which screen is in the form of a solid of revolution and comprises a sifting part and a non-sifting part. The genera-trix of the sifting part has a stepped shape, each step forming a solid of revolution in the form of a hollow conical frustum whose major base faces opposite to the movement of the layer of the loose material under treatment. This con-struction substantially increases the separating properties of the screen in using it in various vibrating centrifugal separation machines.
Description
7'Z6 The presen-t invention relates to devices for sepa-ratillf, various loose rnaterials and has particular re~erence to screens ~or vibra-tinf-, centrifugal scparation macnines.
It can be used ~or sepaIatinf, seeds and various grain materials in agricultuIe and -the food industry ancl lor se-parating various loose mineral materials in the mining, che-mical and other industries.
Known in the art are screens ~or vibrating centrii'uf,al separation macrlines, which screens are designed ~or clean-in~ and/or gradin~ loose materials and are made in the ~orm of a solid o~ revolution (see, ~or exam~le, USSR Inventor's Certificate No. 544476, class B 07 B 1/48). Such a screen has the form o~ a hollow cylinder whose wall has a sifting part and a non-si~ting part. '~'he generatri~ o~ the sur~ace of the si~ting part o~ the screen is a straight line and, there-fore, said surface is plain. Such a screan is mounted on the rotor o~ a vibrating centri~ugal separation machine. ~or convenient mounting, -the screen is diyidad into several parts along the generatrix o~ its sur~ace.
The screen is given a rotary motion and a reciprocat-inp motion simultaneously, thc material to be separa-ted be-ing ~ed onto the inner sur~ace. Due to the rotary motion o the .creen ard the resultant centri~ugal forces, the mate-rial under treatment ~orms an annular layer on the scree~ sur-_ j . ~
1:1417Z~
face. ~uc to t}lC reciprocatin,, mo-tion o -th~ screcn e!l~i the resultailt intertia forces, the annular layer O:e -the material moves on the screen sur~ace alonf, -the a~is oL
screen rotation. As a result, the smaller particles are sifted through the screen apertures to form a separate fraction.
It is known that the na-ture of the movement of loose material on the screen surface substantially influences -the workin~ capacity of the screen. In this connection, the ef~ectiveness of the separation process is deterrnined prl~
marily by two main ~actor5 9 ViZ. the rate of siftin~ o~ small particles through the screen apertures and the rate of move-ment o~ said particles towards the screen sur~ace from inside -the layer o~ the loose material lodging on tne screen sur~ace. The rate o~ si~ting o~ the material particles tnro-ugh the screen apertures depends, in particular, on the ve-locity o~ tneir rela-tive movement on the screen surface.
The rate of movement of the particles towards the screen sur-~ace from inside the material layer depends mainly on the looseness of the material layer (i.e. relative movement of the particles).
~ he velocity of the movement o~ loose material on the screen surface depends, in particular, on the ~requency o~
its ~lbrations which also cause loosening o~ the material 1~417Z~
layer. '~hel-l tlle ~requcncy o~ screen vibration excceds a certain lirtlit, the ratc o~ si~ting oi small particles (1e-creases duc to increase in the velocit~ of their relative snovement which adversely a~fects the possibility o~ the particles getting into the screen apertures~ At the same time the material layer becornes more loosened which pro-motes a greater rate o~ Movement o~ small particles from inside the material layer towards the screen surface. If there were no decrease in -th~ rate of si~ting under these conditions, the working capacity of the screen woula increase with increasing ~requency or amplitude o~ screen vibration to a still ~reater extent than it is achieved with the screens known in the prior art.
~ here~ore, the tendency to increase the working capa-city of the prior-art scresns by intensi~ying the mode o~
their vibration leads chie~ly to undesirablc increase in the velocity of movement o~ the material particles ~Jith consequent decrease in the rate o~ their si~tinp~.
The numerous attempts to boost the loosening o~ the grain layer at the screen vibration ~re~uency favourable ~or si~ting small particles by ~itting pegs o~ variou~ hei~ht, ribs, bars, etc. on the sur~ace o~ the screen si~ting part have faile~ to give a substantial e~fect. Moreover, they have complicated tne construction o~ the screens and reduced tlle ~4~7;Z~ 1:
number of screen apertures~
It is the primary object of the present invention to improve screen separating properties.
It is a further object of the present invention to in~
crease screen working capacity.
It is a still further object of the present invention to increase screen longevity.
It is a still further object of the present invention to reduce specific use of screen making material referred to screen performance in separating loose materials.
It is a still further object of the present invention to reduce specific power consumption in screening loose rnaterials.
These and other objects are achieved by providing a screen in vibrating centrifugal separation machines, which screen is made in the form of a solid of revolution and has a siftinq part designed for sifting loose material and a non-sifting part serving for attaching the sieve to the mounting elements of the machine.
According to the present invention there is provided in a vibrating centrifugal machine separating particles, a screen in the form of a solid of revolution having a stepped surface and adapted for an axial rotary motion and an axial reciprocatng motion, said stepped surface comprising a plur-ality of axially disposed hollow frustums of a cone, the major base of each cone including an inlet for the admis-sion of material so that the material containing particles passes through the interior of said screen, moving from the major to the minor base of each frustum, a major part of tne surface of each frustum having apertures for sifting particles of the material.
Thus according to the invention, the generatrix of the surface of the sifting part of the screen is of stepped form. The resultant shape of the screen surface makes it possible to substantially augment the loosening of the layer of the material under treatment, thereby increasing the rate of movement of small particles from inside the layer towards the screen surface. A further advantage of said shape of the screen surface is that it adds to the rigidity of the screen wall.
Further each step of the generatrix is shaped so that its revolution produces a hollow frustum of a cone whose major base faces opposite to the movement of the material under treatment. This provides for increasing the rate of sifting the particles of loose material through the screen apertures.
Now the invention will be described in detail with reference to the accompanying drawings in which:-Figure l is a general view of the screen constructedaccording to the present invention for use in vibrating centri-fugal separation machines.
Figure 2 is a longitudina-l sectional view of the screen constructed accordinq to the present invention for use in vibrating centrifugal separation machines.
Figure 3 is a fragmentary longitudinal sectional view of the perforated portion of the screen constituting the pre-sent invention and of the layer of loose material on the sur-face thereof.
Figure 4 is a fragmentary longitudinal sectional view ; - 6 -~.-',~.' 11~172,6 of the perforated portion of a p:rior-art screen and of the layer of loose material on the surface thereof.
- 6a -.
ti, . ~. ,. ~.
The screen ior vibrating centrifugal ~eparation ma-chines ~hich const.itutes the presen-t invention comprises a non-siiting part 1 (Figure 1) designed for attachin,~ the screen to the mounting elemen-ts of the machine involved and a si~ting part 2 designed ~or sifting loose material. The generatrix 3 (Figure 2) o~ the surface o~ the screen sifting part 2 (Fip,ure 1) has a stepped shape~ ~ach step 4 (Figure 3) of the p~eneratrix 3 (Figure 2) has pitch "1" and height 'Ih".
The portions of the screen sur~ace corresponding to each step 4 (Figure 3) o~ the generatrix 3 (Figure 2) have smooth junctions curved in a cross section to the radius 'Ir". The pitch "1" i9 several times ~reater than the height 'Ih".
~ he shape and size of holes 5 (~igure 1) in the wall of the screen siftin~ part 2 depend on the screen application.
~he holes 5 may be round, rectangular., square, triangular , oval, etc.
~ he non-sifting part 1 and the sifting part 2 can be made o~ identical or different materials, for example, of steel, or o~ steel and plastics, etc~
For use in a vibrating centri~ugal separation machine, the screen is attached to the mounting elements 6 (Figure 2) of the machine rotor by any method known in the art and is simultaneously rotated and reciprocated by the method appro-priate to the design of the machine involved.
For example, in a machine with a vertical rotor the screen is simultaneously rotatcd about its axis and reci-procated along the aXi5- t~he loose material is ~ed a~ the screen top onto the screen inner sur~ace. Coming into con--tact with the screen sur~ace, the material assumes a rota-ry m~tion ~hich gives rise to centri~ugal forces and the lat-ter c~ause the material to form an annular layer 7 (Fi~ure 2) on the screen surface. The oscillating mover~ent o~ the screen ~11 ~ ,1 er~
sets up~intortia ~orces which impart ~ulsating relative ve-locity to the rna-terial layer 7 due to which the ma-terial moves downwards on the screen sur~ace at the average velo-city Vl.
~ oving from step to step, the material layer 7 becomes substantially de~ormed, which augment9 the loosening of the mater;al and sharply increases the rate of movement of small particles ~rom inside the layer 7 towards the sur~ace o~ the screen. Then said particles are sifted through the holes 5 and collected in the machine to produce a separate ~raction.
~his way o~ loosening the material layer substantially i~-creases the working capacity o~ the screen.
~ he centrifugal forces of the material layer 7 e~ert a comparatively heavy radial pressure onto the screen wall.
However, the steppad construction o~ the screen wall sub-stantially increases the radial rigidity thereo~ and there-by considerably increases the scree~ strength and l~evity.
For convenience in use, the screen constituting the pres~.t invention can be divided in-~o several parts along the generatrix 3 (Figure 2) in such a manner -that putting said parts to~ether will form a surrace o~ revolution.
The e~ficiency of screen performance i9 largely de-pendent on the shape o~ the steps 4 (Figure ~) and the ori-entation thereof in relation to the direction of rnovement of the material layer 7~ The steps 4 must be shaped and ori-entated so -that the maJor base of the hollow conic frustum produced by their revolution faces o~posite to the movement of the material layer 7. l'his condition provides for the required reductio~ of the relative velocity o~ the particles in direct contact with the scraen surface when increase takes place, for example, in the frequency o~ screen vibration, due to which small particles have more possibility o~ gett-in~ into the holes and thereby the rate o~ their sifti~K is increased substantially.
l'his is attributed to the fact that when a particle "m"
(Figure 3) of loose material moves speci~ically under the action of its weight "P" directly on the screen surface, it travel~ not only along the screen axis, but also some distance towards the axis. During such a movement the par-ticle metts additional resistance from the centrifugal inertia force component directed alon~ the ste~, due to which the relative velocity VO of the particle becomes considerably less than the average velocity Vl of the matcrial layer. Unaer these conditions the particle "m" gets into the holes and passes therethrough much more frequently than in the case o~ the prior-art screen, all the rest of the conditions being equal. In the prior-art scroen rnade, ~or exam~lc, itl tho forln ol a vertical hoLlow cylindcr, the paIticle "m"
(FiKure 4) IIIOVeS on thc screen surface along the screen axis speci~ically under the action o~ its weight "P"0 In this screen the centri~ugal force is normal the ~eneratrix o~ its sur~ace. There~ore, with all the rest of the conditions equal, the particle "m" moves in the prior-art screen at a relative velocity V0 which is greater than V0 (Figule ~).
~he velocity V0 (Figure 4) o~ the particle "m" di~ers insignificantly ~rom the average velocity V1 of the mate-rial layer which adversely a~ects both the loosening o~ the material layer and the rate of particle sifting.
With the ge~eratri~ o~ the surface o~ the screen si~t-ing part 2 (~igure 1) comprising the steps 4 (Figure 3) ac-cording to the invention, the velocity o~ the particles on the sur~ace of the layer 7 (Figure ~) can be several times greater than the velocity o~ the particles "m" on the screen surface inasmuch as the upper portions o~ the layer 7 move over t~e proaections o~ the steps 4 and the latter restrict their motion to a smaller extent. ~his condition boosts the looseninK o~ the layer 7 and promotes further increase in the workin6 capacity o~ the screen.
For convenience in manufacture and standardization o~ the screen constituting the present invention, it is de-sirable that the parameters "h" and "1" be -the saMe lor all the steps 4 (Figure 3) o~ the generatrix 3 (Figure 2).
The screen for vibrating centrifugal separation ma-chines which constitutes the present invention has -the ad-vantage that in virtue o~ the stepped separating sur~ace it e~ects more intensive loosening of the layer of the mate-rial under treatment and at the same time possesses a higher rigidity.
Another advantage is that more intensive si~ting of the material is achieved by virtue o~ shaping the screen steps in accordance with the invention. These features substan-tially increase the working capacity and longevity o~ the s¢reen.
It is the greatest advantage of the screen constructed according to the invention that it provides ~or more thorough and intensive si~ting o~ loose materials.
As compared with the screen known in the prior art, the use o~ the screen according to the invention in vibrat-ing centri~ugal separation machines, ~or e~ample, ~or clean-ing and/or grading seeds and various grain materials increases the working capacity o~ the machines involved by 25 to 30 percent without any substantial additional expenses.
It can be used ~or sepaIatinf, seeds and various grain materials in agricultuIe and -the food industry ancl lor se-parating various loose mineral materials in the mining, che-mical and other industries.
Known in the art are screens ~or vibrating centrii'uf,al separation macrlines, which screens are designed ~or clean-in~ and/or gradin~ loose materials and are made in the ~orm of a solid o~ revolution (see, ~or exam~le, USSR Inventor's Certificate No. 544476, class B 07 B 1/48). Such a screen has the form o~ a hollow cylinder whose wall has a sifting part and a non-si~ting part. '~'he generatri~ o~ the sur~ace of the si~ting part o~ the screen is a straight line and, there-fore, said surface is plain. Such a screan is mounted on the rotor o~ a vibrating centri~ugal separation machine. ~or convenient mounting, -the screen is diyidad into several parts along the generatrix o~ its sur~ace.
The screen is given a rotary motion and a reciprocat-inp motion simultaneously, thc material to be separa-ted be-ing ~ed onto the inner sur~ace. Due to the rotary motion o the .creen ard the resultant centri~ugal forces, the mate-rial under treatment ~orms an annular layer on the scree~ sur-_ j . ~
1:1417Z~
face. ~uc to t}lC reciprocatin,, mo-tion o -th~ screcn e!l~i the resultailt intertia forces, the annular layer O:e -the material moves on the screen sur~ace alonf, -the a~is oL
screen rotation. As a result, the smaller particles are sifted through the screen apertures to form a separate fraction.
It is known that the na-ture of the movement of loose material on the screen surface substantially influences -the workin~ capacity of the screen. In this connection, the ef~ectiveness of the separation process is deterrnined prl~
marily by two main ~actor5 9 ViZ. the rate of siftin~ o~ small particles through the screen apertures and the rate of move-ment o~ said particles towards the screen sur~ace from inside -the layer o~ the loose material lodging on tne screen sur~ace. The rate o~ si~ting o~ the material particles tnro-ugh the screen apertures depends, in particular, on the ve-locity o~ tneir rela-tive movement on the screen surface.
The rate of movement of the particles towards the screen sur-~ace from inside the material layer depends mainly on the looseness of the material layer (i.e. relative movement of the particles).
~ he velocity of the movement o~ loose material on the screen surface depends, in particular, on the ~requency o~
its ~lbrations which also cause loosening o~ the material 1~417Z~
layer. '~hel-l tlle ~requcncy o~ screen vibration excceds a certain lirtlit, the ratc o~ si~ting oi small particles (1e-creases duc to increase in the velocit~ of their relative snovement which adversely a~fects the possibility o~ the particles getting into the screen apertures~ At the same time the material layer becornes more loosened which pro-motes a greater rate o~ Movement o~ small particles from inside the material layer towards the screen surface. If there were no decrease in -th~ rate of si~ting under these conditions, the working capacity of the screen woula increase with increasing ~requency or amplitude o~ screen vibration to a still ~reater extent than it is achieved with the screens known in the prior art.
~ here~ore, the tendency to increase the working capa-city of the prior-art scresns by intensi~ying the mode o~
their vibration leads chie~ly to undesirablc increase in the velocity of movement o~ the material particles ~Jith consequent decrease in the rate o~ their si~tinp~.
The numerous attempts to boost the loosening o~ the grain layer at the screen vibration ~re~uency favourable ~or si~ting small particles by ~itting pegs o~ variou~ hei~ht, ribs, bars, etc. on the sur~ace o~ the screen si~ting part have faile~ to give a substantial e~fect. Moreover, they have complicated tne construction o~ the screens and reduced tlle ~4~7;Z~ 1:
number of screen apertures~
It is the primary object of the present invention to improve screen separating properties.
It is a further object of the present invention to in~
crease screen working capacity.
It is a still further object of the present invention to increase screen longevity.
It is a still further object of the present invention to reduce specific use of screen making material referred to screen performance in separating loose materials.
It is a still further object of the present invention to reduce specific power consumption in screening loose rnaterials.
These and other objects are achieved by providing a screen in vibrating centrifugal separation machines, which screen is made in the form of a solid of revolution and has a siftinq part designed for sifting loose material and a non-sifting part serving for attaching the sieve to the mounting elements of the machine.
According to the present invention there is provided in a vibrating centrifugal machine separating particles, a screen in the form of a solid of revolution having a stepped surface and adapted for an axial rotary motion and an axial reciprocatng motion, said stepped surface comprising a plur-ality of axially disposed hollow frustums of a cone, the major base of each cone including an inlet for the admis-sion of material so that the material containing particles passes through the interior of said screen, moving from the major to the minor base of each frustum, a major part of tne surface of each frustum having apertures for sifting particles of the material.
Thus according to the invention, the generatrix of the surface of the sifting part of the screen is of stepped form. The resultant shape of the screen surface makes it possible to substantially augment the loosening of the layer of the material under treatment, thereby increasing the rate of movement of small particles from inside the layer towards the screen surface. A further advantage of said shape of the screen surface is that it adds to the rigidity of the screen wall.
Further each step of the generatrix is shaped so that its revolution produces a hollow frustum of a cone whose major base faces opposite to the movement of the material under treatment. This provides for increasing the rate of sifting the particles of loose material through the screen apertures.
Now the invention will be described in detail with reference to the accompanying drawings in which:-Figure l is a general view of the screen constructedaccording to the present invention for use in vibrating centri-fugal separation machines.
Figure 2 is a longitudina-l sectional view of the screen constructed accordinq to the present invention for use in vibrating centrifugal separation machines.
Figure 3 is a fragmentary longitudinal sectional view of the perforated portion of the screen constituting the pre-sent invention and of the layer of loose material on the sur-face thereof.
Figure 4 is a fragmentary longitudinal sectional view ; - 6 -~.-',~.' 11~172,6 of the perforated portion of a p:rior-art screen and of the layer of loose material on the surface thereof.
- 6a -.
ti, . ~. ,. ~.
The screen ior vibrating centrifugal ~eparation ma-chines ~hich const.itutes the presen-t invention comprises a non-siiting part 1 (Figure 1) designed for attachin,~ the screen to the mounting elemen-ts of the machine involved and a si~ting part 2 designed ~or sifting loose material. The generatrix 3 (Figure 2) o~ the surface o~ the screen sifting part 2 (Fip,ure 1) has a stepped shape~ ~ach step 4 (Figure 3) of the p~eneratrix 3 (Figure 2) has pitch "1" and height 'Ih".
The portions of the screen sur~ace corresponding to each step 4 (Figure 3) o~ the generatrix 3 (Figure 2) have smooth junctions curved in a cross section to the radius 'Ir". The pitch "1" i9 several times ~reater than the height 'Ih".
~ he shape and size of holes 5 (~igure 1) in the wall of the screen siftin~ part 2 depend on the screen application.
~he holes 5 may be round, rectangular., square, triangular , oval, etc.
~ he non-sifting part 1 and the sifting part 2 can be made o~ identical or different materials, for example, of steel, or o~ steel and plastics, etc~
For use in a vibrating centri~ugal separation machine, the screen is attached to the mounting elements 6 (Figure 2) of the machine rotor by any method known in the art and is simultaneously rotated and reciprocated by the method appro-priate to the design of the machine involved.
For example, in a machine with a vertical rotor the screen is simultaneously rotatcd about its axis and reci-procated along the aXi5- t~he loose material is ~ed a~ the screen top onto the screen inner sur~ace. Coming into con--tact with the screen sur~ace, the material assumes a rota-ry m~tion ~hich gives rise to centri~ugal forces and the lat-ter c~ause the material to form an annular layer 7 (Fi~ure 2) on the screen surface. The oscillating mover~ent o~ the screen ~11 ~ ,1 er~
sets up~intortia ~orces which impart ~ulsating relative ve-locity to the rna-terial layer 7 due to which the ma-terial moves downwards on the screen sur~ace at the average velo-city Vl.
~ oving from step to step, the material layer 7 becomes substantially de~ormed, which augment9 the loosening of the mater;al and sharply increases the rate of movement of small particles ~rom inside the layer 7 towards the sur~ace o~ the screen. Then said particles are sifted through the holes 5 and collected in the machine to produce a separate ~raction.
~his way o~ loosening the material layer substantially i~-creases the working capacity o~ the screen.
~ he centrifugal forces of the material layer 7 e~ert a comparatively heavy radial pressure onto the screen wall.
However, the steppad construction o~ the screen wall sub-stantially increases the radial rigidity thereo~ and there-by considerably increases the scree~ strength and l~evity.
For convenience in use, the screen constituting the pres~.t invention can be divided in-~o several parts along the generatrix 3 (Figure 2) in such a manner -that putting said parts to~ether will form a surrace o~ revolution.
The e~ficiency of screen performance i9 largely de-pendent on the shape o~ the steps 4 (Figure ~) and the ori-entation thereof in relation to the direction of rnovement of the material layer 7~ The steps 4 must be shaped and ori-entated so -that the maJor base of the hollow conic frustum produced by their revolution faces o~posite to the movement of the material layer 7. l'his condition provides for the required reductio~ of the relative velocity o~ the particles in direct contact with the scraen surface when increase takes place, for example, in the frequency o~ screen vibration, due to which small particles have more possibility o~ gett-in~ into the holes and thereby the rate o~ their sifti~K is increased substantially.
l'his is attributed to the fact that when a particle "m"
(Figure 3) of loose material moves speci~ically under the action of its weight "P" directly on the screen surface, it travel~ not only along the screen axis, but also some distance towards the axis. During such a movement the par-ticle metts additional resistance from the centrifugal inertia force component directed alon~ the ste~, due to which the relative velocity VO of the particle becomes considerably less than the average velocity Vl of the matcrial layer. Unaer these conditions the particle "m" gets into the holes and passes therethrough much more frequently than in the case o~ the prior-art screen, all the rest of the conditions being equal. In the prior-art scroen rnade, ~or exam~lc, itl tho forln ol a vertical hoLlow cylindcr, the paIticle "m"
(FiKure 4) IIIOVeS on thc screen surface along the screen axis speci~ically under the action o~ its weight "P"0 In this screen the centri~ugal force is normal the ~eneratrix o~ its sur~ace. There~ore, with all the rest of the conditions equal, the particle "m" moves in the prior-art screen at a relative velocity V0 which is greater than V0 (Figule ~).
~he velocity V0 (Figure 4) o~ the particle "m" di~ers insignificantly ~rom the average velocity V1 of the mate-rial layer which adversely a~ects both the loosening o~ the material layer and the rate of particle sifting.
With the ge~eratri~ o~ the surface o~ the screen si~t-ing part 2 (~igure 1) comprising the steps 4 (Figure 3) ac-cording to the invention, the velocity o~ the particles on the sur~ace of the layer 7 (Figure ~) can be several times greater than the velocity o~ the particles "m" on the screen surface inasmuch as the upper portions o~ the layer 7 move over t~e proaections o~ the steps 4 and the latter restrict their motion to a smaller extent. ~his condition boosts the looseninK o~ the layer 7 and promotes further increase in the workin6 capacity o~ the screen.
For convenience in manufacture and standardization o~ the screen constituting the present invention, it is de-sirable that the parameters "h" and "1" be -the saMe lor all the steps 4 (Figure 3) o~ the generatrix 3 (Figure 2).
The screen for vibrating centrifugal separation ma-chines which constitutes the present invention has -the ad-vantage that in virtue o~ the stepped separating sur~ace it e~ects more intensive loosening of the layer of the mate-rial under treatment and at the same time possesses a higher rigidity.
Another advantage is that more intensive si~ting of the material is achieved by virtue o~ shaping the screen steps in accordance with the invention. These features substan-tially increase the working capacity and longevity o~ the s¢reen.
It is the greatest advantage of the screen constructed according to the invention that it provides ~or more thorough and intensive si~ting o~ loose materials.
As compared with the screen known in the prior art, the use o~ the screen according to the invention in vibrat-ing centri~ugal separation machines, ~or e~ample, ~or clean-ing and/or grading seeds and various grain materials increases the working capacity o~ the machines involved by 25 to 30 percent without any substantial additional expenses.
Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a vibrating centrifugal machine separating par-ticles, a screen in the form of a solid of revolution having a stepped surface and adapted for an axial rotary motion and an axial reciprocating motion, said stepped surface comprising a plurality of axially disposed hollow frustums of a cone, the major base of each cone including an inlet for the admission of material in said screen so that the material containing particles passes through the interior cylinder of said screen, moving from the major to the minor base of each frustum, a major part of the surface of each frustum having apertures for sifting particles of the material.
2. A machine according to claim 1 wherein all the frustums are of the same height and base diameter.
3. A machine according to claim 1 wherein each step has pitch and height, the pitch of each step being the same and the height of each step being the same.
4. A machine according to claim 3 wherein the pitch of each step is considerably greater than its height.
5. A machine according to claim 1 wherein each step has pitch and height, the pitch of each step being considerably greater than its height.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000330995A CA1141726A (en) | 1979-07-03 | 1979-07-03 | Screen for vibrating centrifugal separation machines |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000330995A CA1141726A (en) | 1979-07-03 | 1979-07-03 | Screen for vibrating centrifugal separation machines |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1141726A true CA1141726A (en) | 1983-02-22 |
Family
ID=4114601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000330995A Expired CA1141726A (en) | 1979-07-03 | 1979-07-03 | Screen for vibrating centrifugal separation machines |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1141726A (en) |
-
1979
- 1979-07-03 CA CA000330995A patent/CA1141726A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0419033B1 (en) | Improvements relating to vibratory sifters | |
| EP2890505B1 (en) | Vibrating screen | |
| US9694391B1 (en) | Adjustable split weight gyratory sifter | |
| US3819050A (en) | Feed distributor for screening machine | |
| EP0411803B1 (en) | A rotating screen | |
| EP0793544B1 (en) | Apparatus for sieving a particulate material | |
| AU644710B2 (en) | A rotary screen device | |
| US3650401A (en) | Apparatus for vibrating a material separator | |
| CA1141726A (en) | Screen for vibrating centrifugal separation machines | |
| US4247392A (en) | Screen for vibrating centrifugal separation machines | |
| CN214766808U (en) | Improved generation multistage linear vibration sieve | |
| CN210230667U (en) | Multipurpose spiral separator | |
| DE102014204595B3 (en) | Sieving machine for classifying screenings, in particular tumble screening machine | |
| GB2069359A (en) | Screen for Vibrating Centrifugal Separation Machines | |
| CN209577335U (en) | Material separator | |
| RU2672697C1 (en) | Method for separation of bulk materials into fractions by method of throwing mixture of particles at same speed and device therefor | |
| RU2184624C2 (en) | Rotating probability screen | |
| CN206967313U (en) | Processing spray, the pre-sifted dust arrester of ball blast abrasive material | |
| SU954045A1 (en) | Centrifugal grain cleaning machine | |
| CN107649371A (en) | A kind of double-layer spiral vibratory sieve | |
| US1236256A (en) | Grader and separator. | |
| CN215695774U (en) | Drying and sieving device for thermosetting powder coating powder | |
| CN220611323U (en) | Superfine grading equipment for dry materials | |
| CN210614299U (en) | Multi-node type vibrating screen | |
| JPH05301080A (en) | Removing equipment for dust of crushed sand |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |