CA1062191A - Device with screw conveyer for discharging bulk material - Google Patents
Device with screw conveyer for discharging bulk materialInfo
- Publication number
- CA1062191A CA1062191A CA289,672A CA289672A CA1062191A CA 1062191 A CA1062191 A CA 1062191A CA 289672 A CA289672 A CA 289672A CA 1062191 A CA1062191 A CA 1062191A
- Authority
- CA
- Canada
- Prior art keywords
- drum
- screw
- conveyer
- screw conveyer
- apertures
- 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
- Filling Or Emptying Of Bunkers, Hoppers, And Tanks (AREA)
Abstract
ABSTRACT
A device for discharging bulk material is described, consisting of a conveyer screw surrounded by a rotary drum having apertures evenly distributed over its cylindrical face. The drum is moved transversely during its rotation, so that the apertures describe a trochoidal path, during which a layer of the bulk material is gradually worked off and admitted through the apertures into the drum to be moved on therein by the conveyer screw.
A device for discharging bulk material is described, consisting of a conveyer screw surrounded by a rotary drum having apertures evenly distributed over its cylindrical face. The drum is moved transversely during its rotation, so that the apertures describe a trochoidal path, during which a layer of the bulk material is gradually worked off and admitted through the apertures into the drum to be moved on therein by the conveyer screw.
Description
~ ~.o~
~he present invention relates-to a device for discharging bulk material from a stock thereof, The bulk materia~ consists of solid material which is divided up into small particles, grains, powder or similar and which has sNch properties that it does not flow easily by itself but must be aided mechanically. Examples of such material are cut wood chips for the manufacture of cellulose, cellulose pulp, corn, sand, coal etc. ~or the discharge of such ma~erial it is common to use rotary screw conveyers working in the stock and forwarding the material towards an outlet.
When the screw conveyer is stationary, the discharging operation will be uneven on account of material flowing forth more freely from certain directions, and in some places there may be dead zones with no or very slow motion of the material. This can be counteracted by making the screw conveyer movable at right angles to it~ shaft.
~owever, such a measure will not provide any satisfsctory solution of the problem forming the basis of the present invention, YiZ.
distributing the discharging effect as effectively as possible over a layer of the stock, so that the mass descends at the same rate everywhere and without mass portions of different storage periods being mingled.
According to the present invention there is provided a device for discharging bulk material from a store thereof comprising a rotary screw conveyer movable transversely to its own axis, wherein the screw ~ conveyer is surrounded by a drum which is rotatable independently of - the screw conveyer and which is provided with inlet apertures distributed i 25 over the periphery and along the length of the cylindrical face of the drum, which aperture~, during the combined rotatio~ and~transverse displacément of the drum, dig into a layer of the p~p material and transfer the material into the drum to be displaced by the screw conveyer.
~he completion Or the screw conveyer with a surrounding drum also bringæ about advantages in respect of the construction and working - mode of the conveyer screw, the same being relieved of the pressure of the mas~ layer; also it need not be given a varying thread pitch, a measure ~k `
~ 2 - ' ' '' , - . . . .
~0~
which earlier has been resorted to in an attempt to have the disch æ ge properly distributed along the length of the screw.
The invention will be described further~ by way of example, with reference to the accompanying drawings, in which: -Fig. 1 i8 a vertical section ~iew of a silo having at its base a discharging device constructed according to the invention;
Fig. 2 is a side view taken from the line II - II in Fig. 1;
Fig. 3 is a cross-sectional view taken along the line III - III
in ~ig. 1;
~ig. 4 shows a modified embodiment of the disch æ ging device placed below an open store; and Fig. 5 is a cross-sectional view taken along the line V - V in Fig. 4.
In ~ig. 1, 11 designates the vertical walls of a silo forming a shaft of a rectangul æ cross-section adapted to be filled at the top with a finely comminuted material and emptied at the bottom. The filling 13 forms a tempor æy stock in which mixing is not desired, and the filling should descend evenly over the whole cross-section so that the retention period o f the individual particles is as uniform as possible.
Inserted in the silo, immediately above the base 15 thereof, is a horizontal screw conveyer comprising a shaft 17 and a screw blade 19 attached thereto~ which forms a continuous helical face of a constant pitch.
One end of the shaft 17 is journalled in a be æing 21 and carries a chain wheel 23 which is coupled to an electric driving motor 29 by means of a chain 25 and a worm ge æ 27. The bearin~ 21 and said driving means are mounted on a carriage 31 whioh by means of shoes 33 (or wheels as an alternative( runs upon a horizontal track 35 extending in a duct at the side of the silo and along the entire length of the silo. The opposite end of the shaft 17 is journalled in a bearing 37 running on a track 39 parallel to the tra¢k 35 and located on a ledge at the outer side of a horizontal 3 du¢t 41. Said duct 41 also houses a belt conveyer 43 situated beneath the ~ . - .
end of the screw conveyer and upon which the material dischæ ged from-' ~
.
~06~
the silo by the screw conveyer is carried away.
The carriage 31 is movable back and forth along the track 35 by means of wires 45 connected to a motor-driven winch (not shown).
Corresponding wires are attached to the bearing 37 to displace the bearing 37 in unison with the carriage 31, so that the shaft 17 is maintained in correct alignment. Of course, the synchronous drive can be effected in some other way, e.g. by engagement with rac~s.
The screw conveyer i8 surrounded by a cylindrical drum 47 which extends over the entire width of the silo and the ends of which project into the above-mentioned ducts. The drum 47 is concentric with the shaft 17 and its outermost ends are supported upon the shaft 17. One end of the drum has a chain wheel 49 which, by means of a chain 51, is coupled to a hydraulic motor 53 placed upon the carriage 31. By means of said motor the drum 47 is rotated independently of, considerably slower than, and usually oppositely dirested to, the rotation of the screw conveyer 17, 19. At its opposite, undriven end, the drum 47 has an outlet formed by slots 55 between axially directed laths 57 connecting the end of the ~- drum to an end disc 59 which is journalled upon the shaft 17.
A plurality of inlet apert res 61 having the shape of axially (or obliquely) directed slits are cut in the drum 47, which apertures 61 are distributed over the whole or substantially the whole length - of the drum extending between the walls 11, and also distri~uted around .~ .
the circumference thereof. In every cross-section of the drum there is ; at least one inlet aperture, or usually several apertures, in which 25 latter case these preferably are e~enly spaced around the circumference.
Slits 61 adJacent each other in the axial direction are offset mutually in the peripheral direction. Slit~ 61 of different axial positions may overlap partially~ but in this ca$e it i8 particularly important to place them at a sufficient peripheral interval so as not to weaken the drum 47. In the various cross-sections of the drum 47 the total ; . ~ ' .
.
. .
.
~ 4 -- . - , . , ... : ., .. :
0~
peripheral extent of the slits 61 i9 substantially the 6ame.
Preferably all slits 61 æe mutually of the same size~and configuration.
The dimensions thereof should be chosen with regard to the size of the particles to pass therethrough.
In operation~ when the carriage 31 is moved slowly along its track and the drum 47 is rotated by means of the motor 53, each of the inlet slits 61 describes a trochoidal path through a horizontal layer of the bulk material, For one direction of movement of the carriage, a part of said path is indicated by the curve 63 in Fig. 2, and when the carriage is moved in the opposite direction, the path is indicated by the curve 65. During this combined motion of rotation-and lateral displacement the comminuted particles are pushed through the ~-slits 61 of the drum 47, and the edges of the slits 61 perform a digging operation to loosen and separate particles from the b-lk sufficiently to enable them to pass into the drum 47. The conveyer screw is driven at such a speed that the material entering the drum 47 does not fill up the drum to more than a fraction of the cross-section, e.g. half thereof at the most. Thus, when the slits 61 take a position at the upper half of the drum 47, where the rate of passage of material through the slits is at maximum, the particles do not encounter any hindrance from material previously introduced into the drum 47, but drop easily through the slits 61 regardless of their location along the length of the drum 47. Thereby it is ensured that the mass layer in which the drum 47 moves,is removed uniformly, in contrast to the situation with a co~veyer screw without a drum, wherein the mags is admitted unequally along the length thereof.
~he drum 47 takes up the pressure of the weight of the material overlying it, and due to its rigidity the drum resists this pressure without substantial deflection, so that the screw conveyer ~ is relieved, and the shaft thereof may be made of comparatively ~mall diameter. Also, the ¢onveyer screw can be driven rapidly with a low - . , - - . ' . .. ' - .: : . , .. , .: .-,, .
power consumption due to the fact that it merely conveys the material in the drum towards the outlet and does not perform any futile agitation of the material in the vicinity thereof, as i8 the case when the screw is placed in direct contact with the bulk and is closely surrounded thereby on all sides. Due thereto the material is spared also, so that the particles are not broken or worn.
~he device shown in Figs. 4 and 5 serves to withdraw bulk material from the bottom layer of an open store. Therein uniform descent can be had merely at the central parts of the store, but not at the sloping sides. The design is generally similar to that shown in ~igs. 1 - 3. ~owever, at the inlet apertures there are extensions projecting beyond the cylindrical face of the drum and which form buckets 69 which, during the rotation, rake bulk material through the slits 61 into the drum. In a simplified design the buckets 69 may be formed by bending out the sheet metal material of the drum along one longitudinal edge of the slits 61. Also, the outlet end of the - ~rum is either open or terminates with an apertured head 71 throughwhich the discharged material leaves the drum. ~he drum is supported by an exterior bearing 73 which runs on the track 39, and the shaft 17 of the sorew conveyer is journalled in the head 71. --Of course, the above-described embodiments may be modified in various respects. For instance, the drum may be supported separately, in which case the conveyer screw may be placed eccentrically therein. Also, the drive of the drum may be at the end opposite to the end where the conveyer screw is driven. In tpis case it will be possible to use dIiving mechanisms concentric to the drum and-the screw~ e.g. hydraulic hub motors. If the base 15 is sloping, the drum and the conveyer screw may also be set at an inclination Or a smaller or greatér angle to the horizontal plane. Furthermore, the 3 invention can be applied to a concentric Rrrangement, wherein the drum and the screw~ instead of being displaceable parallel to - . , . . , , :
. . .
. . .
" ' ' ' . ' , - : , 10~ 3~.
themselves, swing about ~ vertical axis. In this case the carriage 31 runs on a track 35 that is~circular, and ~he outlet end of the drum is located centrall~ of the silo and i8 substantially stationary. ~hen, in order to get a uniform di~schargej the tot'al peripheral extent of the outlet apertures 31 in the various cross-sections of the drum should be made greater according to their distances from the axis of the swinging motion increase. mis can be attained by placing the slits gradually closer to each other and/or making them gradually wider towards the outer end of,the drum.
, .: , ,., ' ' , ' ', '
~he present invention relates-to a device for discharging bulk material from a stock thereof, The bulk materia~ consists of solid material which is divided up into small particles, grains, powder or similar and which has sNch properties that it does not flow easily by itself but must be aided mechanically. Examples of such material are cut wood chips for the manufacture of cellulose, cellulose pulp, corn, sand, coal etc. ~or the discharge of such ma~erial it is common to use rotary screw conveyers working in the stock and forwarding the material towards an outlet.
When the screw conveyer is stationary, the discharging operation will be uneven on account of material flowing forth more freely from certain directions, and in some places there may be dead zones with no or very slow motion of the material. This can be counteracted by making the screw conveyer movable at right angles to it~ shaft.
~owever, such a measure will not provide any satisfsctory solution of the problem forming the basis of the present invention, YiZ.
distributing the discharging effect as effectively as possible over a layer of the stock, so that the mass descends at the same rate everywhere and without mass portions of different storage periods being mingled.
According to the present invention there is provided a device for discharging bulk material from a store thereof comprising a rotary screw conveyer movable transversely to its own axis, wherein the screw ~ conveyer is surrounded by a drum which is rotatable independently of - the screw conveyer and which is provided with inlet apertures distributed i 25 over the periphery and along the length of the cylindrical face of the drum, which aperture~, during the combined rotatio~ and~transverse displacément of the drum, dig into a layer of the p~p material and transfer the material into the drum to be displaced by the screw conveyer.
~he completion Or the screw conveyer with a surrounding drum also bringæ about advantages in respect of the construction and working - mode of the conveyer screw, the same being relieved of the pressure of the mas~ layer; also it need not be given a varying thread pitch, a measure ~k `
~ 2 - ' ' '' , - . . . .
~0~
which earlier has been resorted to in an attempt to have the disch æ ge properly distributed along the length of the screw.
The invention will be described further~ by way of example, with reference to the accompanying drawings, in which: -Fig. 1 i8 a vertical section ~iew of a silo having at its base a discharging device constructed according to the invention;
Fig. 2 is a side view taken from the line II - II in Fig. 1;
Fig. 3 is a cross-sectional view taken along the line III - III
in ~ig. 1;
~ig. 4 shows a modified embodiment of the disch æ ging device placed below an open store; and Fig. 5 is a cross-sectional view taken along the line V - V in Fig. 4.
In ~ig. 1, 11 designates the vertical walls of a silo forming a shaft of a rectangul æ cross-section adapted to be filled at the top with a finely comminuted material and emptied at the bottom. The filling 13 forms a tempor æy stock in which mixing is not desired, and the filling should descend evenly over the whole cross-section so that the retention period o f the individual particles is as uniform as possible.
Inserted in the silo, immediately above the base 15 thereof, is a horizontal screw conveyer comprising a shaft 17 and a screw blade 19 attached thereto~ which forms a continuous helical face of a constant pitch.
One end of the shaft 17 is journalled in a be æing 21 and carries a chain wheel 23 which is coupled to an electric driving motor 29 by means of a chain 25 and a worm ge æ 27. The bearin~ 21 and said driving means are mounted on a carriage 31 whioh by means of shoes 33 (or wheels as an alternative( runs upon a horizontal track 35 extending in a duct at the side of the silo and along the entire length of the silo. The opposite end of the shaft 17 is journalled in a bearing 37 running on a track 39 parallel to the tra¢k 35 and located on a ledge at the outer side of a horizontal 3 du¢t 41. Said duct 41 also houses a belt conveyer 43 situated beneath the ~ . - .
end of the screw conveyer and upon which the material dischæ ged from-' ~
.
~06~
the silo by the screw conveyer is carried away.
The carriage 31 is movable back and forth along the track 35 by means of wires 45 connected to a motor-driven winch (not shown).
Corresponding wires are attached to the bearing 37 to displace the bearing 37 in unison with the carriage 31, so that the shaft 17 is maintained in correct alignment. Of course, the synchronous drive can be effected in some other way, e.g. by engagement with rac~s.
The screw conveyer i8 surrounded by a cylindrical drum 47 which extends over the entire width of the silo and the ends of which project into the above-mentioned ducts. The drum 47 is concentric with the shaft 17 and its outermost ends are supported upon the shaft 17. One end of the drum has a chain wheel 49 which, by means of a chain 51, is coupled to a hydraulic motor 53 placed upon the carriage 31. By means of said motor the drum 47 is rotated independently of, considerably slower than, and usually oppositely dirested to, the rotation of the screw conveyer 17, 19. At its opposite, undriven end, the drum 47 has an outlet formed by slots 55 between axially directed laths 57 connecting the end of the ~- drum to an end disc 59 which is journalled upon the shaft 17.
A plurality of inlet apert res 61 having the shape of axially (or obliquely) directed slits are cut in the drum 47, which apertures 61 are distributed over the whole or substantially the whole length - of the drum extending between the walls 11, and also distri~uted around .~ .
the circumference thereof. In every cross-section of the drum there is ; at least one inlet aperture, or usually several apertures, in which 25 latter case these preferably are e~enly spaced around the circumference.
Slits 61 adJacent each other in the axial direction are offset mutually in the peripheral direction. Slit~ 61 of different axial positions may overlap partially~ but in this ca$e it i8 particularly important to place them at a sufficient peripheral interval so as not to weaken the drum 47. In the various cross-sections of the drum 47 the total ; . ~ ' .
.
. .
.
~ 4 -- . - , . , ... : ., .. :
0~
peripheral extent of the slits 61 i9 substantially the 6ame.
Preferably all slits 61 æe mutually of the same size~and configuration.
The dimensions thereof should be chosen with regard to the size of the particles to pass therethrough.
In operation~ when the carriage 31 is moved slowly along its track and the drum 47 is rotated by means of the motor 53, each of the inlet slits 61 describes a trochoidal path through a horizontal layer of the bulk material, For one direction of movement of the carriage, a part of said path is indicated by the curve 63 in Fig. 2, and when the carriage is moved in the opposite direction, the path is indicated by the curve 65. During this combined motion of rotation-and lateral displacement the comminuted particles are pushed through the ~-slits 61 of the drum 47, and the edges of the slits 61 perform a digging operation to loosen and separate particles from the b-lk sufficiently to enable them to pass into the drum 47. The conveyer screw is driven at such a speed that the material entering the drum 47 does not fill up the drum to more than a fraction of the cross-section, e.g. half thereof at the most. Thus, when the slits 61 take a position at the upper half of the drum 47, where the rate of passage of material through the slits is at maximum, the particles do not encounter any hindrance from material previously introduced into the drum 47, but drop easily through the slits 61 regardless of their location along the length of the drum 47. Thereby it is ensured that the mass layer in which the drum 47 moves,is removed uniformly, in contrast to the situation with a co~veyer screw without a drum, wherein the mags is admitted unequally along the length thereof.
~he drum 47 takes up the pressure of the weight of the material overlying it, and due to its rigidity the drum resists this pressure without substantial deflection, so that the screw conveyer ~ is relieved, and the shaft thereof may be made of comparatively ~mall diameter. Also, the ¢onveyer screw can be driven rapidly with a low - . , - - . ' . .. ' - .: : . , .. , .: .-,, .
power consumption due to the fact that it merely conveys the material in the drum towards the outlet and does not perform any futile agitation of the material in the vicinity thereof, as i8 the case when the screw is placed in direct contact with the bulk and is closely surrounded thereby on all sides. Due thereto the material is spared also, so that the particles are not broken or worn.
~he device shown in Figs. 4 and 5 serves to withdraw bulk material from the bottom layer of an open store. Therein uniform descent can be had merely at the central parts of the store, but not at the sloping sides. The design is generally similar to that shown in ~igs. 1 - 3. ~owever, at the inlet apertures there are extensions projecting beyond the cylindrical face of the drum and which form buckets 69 which, during the rotation, rake bulk material through the slits 61 into the drum. In a simplified design the buckets 69 may be formed by bending out the sheet metal material of the drum along one longitudinal edge of the slits 61. Also, the outlet end of the - ~rum is either open or terminates with an apertured head 71 throughwhich the discharged material leaves the drum. ~he drum is supported by an exterior bearing 73 which runs on the track 39, and the shaft 17 of the sorew conveyer is journalled in the head 71. --Of course, the above-described embodiments may be modified in various respects. For instance, the drum may be supported separately, in which case the conveyer screw may be placed eccentrically therein. Also, the drive of the drum may be at the end opposite to the end where the conveyer screw is driven. In tpis case it will be possible to use dIiving mechanisms concentric to the drum and-the screw~ e.g. hydraulic hub motors. If the base 15 is sloping, the drum and the conveyer screw may also be set at an inclination Or a smaller or greatér angle to the horizontal plane. Furthermore, the 3 invention can be applied to a concentric Rrrangement, wherein the drum and the screw~ instead of being displaceable parallel to - . , . . , , :
. . .
. . .
" ' ' ' . ' , - : , 10~ 3~.
themselves, swing about ~ vertical axis. In this case the carriage 31 runs on a track 35 that is~circular, and ~he outlet end of the drum is located centrall~ of the silo and i8 substantially stationary. ~hen, in order to get a uniform di~schargej the tot'al peripheral extent of the outlet apertures 31 in the various cross-sections of the drum should be made greater according to their distances from the axis of the swinging motion increase. mis can be attained by placing the slits gradually closer to each other and/or making them gradually wider towards the outer end of,the drum.
, .: , ,., ' ' , ' ', '
Claims (13)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A device for discharging bulk material from a store thereof comprising a rotary screw conveyer movable transversely to its own axis, wherein a drum is provided surrounding the screw conveyor which drum is rotatable independently of the screw conveyer and is provided with inlet apertures distributed over its periphery and along the length of its cylindrical surface, which apertures, during the combined rotation and transverse displacement of the drum, are capable of digging into a layer of the bulk material and transferring the material into the drum to be displaced by the screw conveyer.
2. A device according to claim 1, wherein the inlet apertures are shaped as axially or obliquely extending slits.
3. A device according to claim 1, wherein there is at least one inlet aperture in each cross-section of the drum, except for its outermost ends.
4. A device according to claim 3, wherein inlet apertures sit-uated in the same cross-section of the drum are equally spaced in the peripheral direction.
5. A device according to claim 4, in which the drum is displaced parallel to its longitudinal axis, and the total peripheral extent of the apertures is substantially the same in the various cross-sections of the drum.
6. A device according to claim 4, in which the drum is swingable about a vertical axis, and the total peripheral extent of the inlet aper-tures in the various cross-sections of the drum are greater according to their distances from said axis increase.
7. A device according to claim 1, wherein the drum is journalled at both ends upon the shaft of the conveyer screw.
8. A device according to claim 1, wherein one end of the drum is supported by an exterior bearing which is displaceably supported upon a fixed bedding.
9. A device according to claim 7 or 8, wherein one end of the shaft of the conveyer screw is journalled in one end of the drum.
10. A device according to claim 7, wherein the drum has an outlet at one end, which is situated inwardly of its bearing upon the shaft of the screw conveyer.
11. A device according to claim 1, wherein the drum is driven by a motor other than the drive motor of the screw conveyer.
12. A device according to claim 1, wherein the drum and the screw conveyer are driven at adjacent ends.
13. A device according to claim 11 or 12, wherein the two motors are placed upon a carriage which is displaceable in a straight or curved path extending perpendicularly to the axes of the drum and the screw con-veyer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA289,672A CA1062191A (en) | 1977-10-27 | 1977-10-27 | Device with screw conveyer for discharging bulk material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA289,672A CA1062191A (en) | 1977-10-27 | 1977-10-27 | Device with screw conveyer for discharging bulk material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1062191A true CA1062191A (en) | 1979-09-11 |
Family
ID=4109878
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA289,672A Expired CA1062191A (en) | 1977-10-27 | 1977-10-27 | Device with screw conveyer for discharging bulk material |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1062191A (en) |
-
1977
- 1977-10-27 CA CA289,672A patent/CA1062191A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2860598A (en) | Production of granulated materials consisting of a core and one or more shells | |
| GB1563057A (en) | Device for discharging bulk material | |
| US5176295A (en) | Discharge apparatus for bins | |
| JP5856037B2 (en) | Metering feeder | |
| CN207524333U (en) | Batch hopper | |
| CN207340495U (en) | A kind of sweet potato class seed sowing machine | |
| CN206511546U (en) | Two-way blanking auger | |
| JPS5849464B2 (en) | Barasairiyo Bunker | |
| CA1041964A (en) | Bulk bin delivery and metering apparatus | |
| CA1062191A (en) | Device with screw conveyer for discharging bulk material | |
| US3710960A (en) | Bottom discharge means for silo | |
| CA2038153C (en) | Discharge apparatus for bins | |
| US4245933A (en) | Silo installation and apparatus for loading and unloading a silo | |
| CN216468512U (en) | Sowing mechanism and unmanned aerial vehicle | |
| US4564317A (en) | Silo for storing solidifying loose material, especially flue dust | |
| US2860790A (en) | Feeder for filling silos and like structures | |
| FI80248C (en) | UTMATNINGSANORDNING FOER SILO. | |
| US4330233A (en) | Flow control apparatus for silage unloader | |
| CA2032622A1 (en) | Silo with a discharge means | |
| US4264258A (en) | Rotatable screw conveyor for discharging chip silos | |
| CN2348927Y (en) | Wet type combined wheel mill | |
| RU2107044C1 (en) | Feeder of flowing and agglomerating components of glass charge | |
| RU2311750C2 (en) | Material grinding method and grinder | |
| SU1551633A2 (en) | Feeder for loose materials | |
| RU2005077C1 (en) | Rotary head for laying and tightening building mixture |