EP0224621A1 - Powder flow control valve - Google Patents

Powder flow control valve Download PDF

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Publication number
EP0224621A1
EP0224621A1 EP85308409A EP85308409A EP0224621A1 EP 0224621 A1 EP0224621 A1 EP 0224621A1 EP 85308409 A EP85308409 A EP 85308409A EP 85308409 A EP85308409 A EP 85308409A EP 0224621 A1 EP0224621 A1 EP 0224621A1
Authority
EP
European Patent Office
Prior art keywords
boundary surface
flow path
pressure
valve
powder flow
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.)
Withdrawn
Application number
EP85308409A
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German (de)
French (fr)
Inventor
Philip John Lloyd
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Portals Engineering Ltd
Original Assignee
Portals Engineering Ltd
Loughborough Consultants Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to GB08412802A priority Critical patent/GB2158813B/en
Application filed by Portals Engineering Ltd, Loughborough Consultants Ltd filed Critical Portals Engineering Ltd
Priority to EP85308409A priority patent/EP0224621A1/en
Publication of EP0224621A1 publication Critical patent/EP0224621A1/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D88/00—Large containers
    • B65D88/54—Large containers characterised by means facilitating filling or emptying
    • B65D88/72—Fluidising devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D90/00—Component parts, details or accessories for large containers
    • B65D90/54—Gates or closures

Definitions

  • This invention relates to a powder flow control valve and to a method of controlling powder flow.
  • powder refers to materials made up of discrete particles. As will be clear from the description below the term includes a relatively fine powder such as flour and also a granu­lar material such as granulated salt (5 mm maximum particle dimension) or agglomerated coffee powder (3 mm maximum particle dimension).
  • a container When a container is to be filled with a powder, it may be desirable to measure the weight of powder accurately. For example in the food industry it may be necessary to fill a container with a measured weight of powder such as coffee or milk powder. It is desirable that the measurement of the weight of powder should be as accurate as possible since a minimum quantity of powder must be provided in the container but once that minimum weight is reached any extra powder in the container is wasted.
  • valve that can operate reliably over a pro­longed period and that is not too difficult to maintain and in particular clean.
  • the valve may also have to be sterilisable.
  • a powder flow control valve in which a powder flow path is surrounded by a perforated boundary surface and means are provided for creating a drop in pressure across the boundary surface with the higher pressure on the powder flow path side of the boundary surface.
  • the means for creating a drop in pressure across the boundary surface preferably operates by reducing the pressure on the opposite side of the boundary surface to the powder flow path without reducing (or without reduc­ing so much) the pressure along the powder flow path.
  • it could operate by increasing the pressure along the powder flow path with­out increasing (or without increasing so much) the pressure on the opposite side of the boundary surface.
  • the cross-sectional area of the flow path sur­rounded by the perforated boundary surface preferably decreases in the downstream direction.
  • the boundary surface has rotational symmetry and preferably includes a substantially frusto-conical portion with the smaller diameter portion downstream of the large diameter portion.
  • the portion of the powder flow path surrounded by the perforated boundary surface is advantageously sub­stantially vertical.
  • valve may be used to control the flow of a wide variety of powders including, for example, flour, powdered milk, agglomerated coffee powder and granulated salt.
  • the perforated boundary surface may be made of a porous material, for example sintered metal powder, glass or a plastics material, or may be made by a compo­nent with apertures formed therein at a multiplicity of predetermined locations. In the latter case the locations are preferably evenly distributed around the boundary surface.
  • means for creating a pressure drop across the boundary surface with the higher pressure on the powder flow path side of the boundary surface may be provided for creating a pressure rise across the boundary surface with the lower pressure on the powder flow path side of the boundary surface.
  • a method of controlling the flow of a powder in which a portion of the path along which powder flows is surrounded by a perforated boundary surface and powder flow is stopped by creating a drop in pressure across the boundary surface with the higher pressure on the powder flow path side of the boundary surface.
  • the control valve 1 is sited at the bottom of a shaft 2 of circular cross-section and includes a frusto-­conical part 3 made of porous plastics material which in this particular example is that sold by Porvair Ltd. under the trademark VYON. Immediately below the frusto-conical part 3 is a cylindrical part 4 leading to an outlet 5 of the valve. A plenum chamber 6 is defined between the outside of the frusto-conical part 3 and the walls of the shaft 2. The plenum chamber 6 is connected to a pumping system when can be arranged to suck air out of, or force air into, the chamber 6.
  • the pumping system comprises a duct 11 which is connected, on the one hand, via a duct 7 and a valve 8 to a reservoir 9 of low pressure air maintained at low pressure by a pump 10 and, on the other hand, via a duct 12 and a valve 13 to a compressed air cylinder 14.
  • the valve 1 can therefore be used very effec­tively to control powder flow.
  • the shaft 2 had an internal diameter d of 60 mm
  • the frusto-conical part 3 had a height h of 42 mm and a minimum internal diameter d2 of 15 mm.
  • the inclination ⁇ of the frusto-conical boundary surface to the horizontal was 60°.
  • the powder used was agglomerated coffee which when subjected to a sieve analysis gave the results shown in the table below:
  • the porous material defining the boundary surface had a mean pore size of 70 microns and a thickness of 4.75 mm. The thickness is not however believed to be particularly significant.
  • the porous material allowed a flow of air of 3.5 cm3/m2/min at a pressure of 3 kN/m2.
  • the pressure in the plenum chamber 6 was 15" Hg (about 51 kN/m2) be­low atmospheric pressure and there was an air flow rate of 48 litres per minute (at atmospheric pressure).
  • the pressure in the plenum chamber was 6 psi (about 41 kN/m2) above atmospheric pressure and there was an air flow rate of 47 litres per minute (at atmospheric pressure).
  • valve was also tested with powdered milk and proved entirely satisfactory. Nonetheless it should be understood that the dimensions of the valve may need to be altered for different powders and in particular the dimensions d2 may need to be varied. It is also possible to omit the cylindrical part 4 at the outlet of the valve without affecting the operation of the valve.
  • boundary surface is frusto-conical
  • other shapes of boundary surface could be employed.
  • a surface of inverted pyramid shape could be used, or even a cylindrical shape.
  • valve has been described almost exclusively in relation to controlling the flow of food powders it will be understood that applications of the valve may also be found outside the food industry.

Abstract

A powder flow control valve (1) has a powder flow path surrounded by a frusto-conical perforated boundary surface (3). Means are provided for creating a drop in pressure across the boundary surface (3) with the higher pressure on the powder flow path side of the boundary surface.

Description

  • This invention relates to a powder flow control valve and to a method of controlling powder flow.
  • The term "powder" as used herein refers to materials made up of discrete particles. As will be clear from the description below the term includes a relatively fine powder such as flour and also a granu­lar material such as granulated salt (5 mm maximum particle dimension) or agglomerated coffee powder (3 mm maximum particle dimension).
  • When a container is to be filled with a powder, it may be desirable to measure the weight of powder accurately. For example in the food industry it may be necessary to fill a container with a measured weight of powder such as coffee or milk powder. It is desirable that the measurement of the weight of powder should be as accurate as possible since a minimum quantity of powder must be provided in the container but once that minimum weight is reached any extra powder in the container is wasted.
  • Various problems have to be overcome in producing an accurate measurement of the powder but one problem is providing a valve that can operate reliably over a pro­longed period and that is not too difficult to maintain and in particular clean. The valve may also have to be sterilisable.
  • According to the invention there is provided a powder flow control valve in which a powder flow path is surrounded by a perforated boundary surface and means are provided for creating a drop in pressure across the boundary surface with the higher pressure on the powder flow path side of the boundary surface.
  • When the pressure drop is created powder flowing through the valve is drawn towards the boundary surface and held there so that flow of powder through the valve is terminated. A major advantage of this design is that there need be no moving parts in the powder flow path resulting in a very simple design which is also easy to clean.
  • The means for creating a drop in pressure across the boundary surface preferably operates by reducing the pressure on the opposite side of the boundary surface to the powder flow path without reducing (or without reduc­ing so much) the pressure along the powder flow path. Alternatively, but less desirably, it could operate by increasing the pressure along the powder flow path with­out increasing (or without increasing so much) the pressure on the opposite side of the boundary surface.
  • The cross-sectional area of the flow path sur­rounded by the perforated boundary surface preferably decreases in the downstream direction.
  • Preferably the boundary surface has rotational symmetry and preferably includes a substantially frusto-conical portion with the smaller diameter portion downstream of the large diameter portion. In use the portion of the powder flow path surrounded by the perforated boundary surface is advantageously sub­stantially vertical.
  • The precise dimensions and shape of the boundary surface may be chosen by experiment and different dimen­sions and shapes may be used for different powders. In this way the valve may be used to control the flow of a wide variety of powders including, for example, flour, powdered milk, agglomerated coffee powder and granulated salt.
  • The perforated boundary surface may be made of a porous material, for example sintered metal powder, glass or a plastics material, or may be made by a compo­nent with apertures formed therein at a multiplicity of predetermined locations. In the latter case the locations are preferably evenly distributed around the boundary surface.
  • In addition to providing means for creating a pressure drop across the boundary surface with the higher pressure on the powder flow path side of the boundary surface means may be provided for creating a pressure rise across the boundary surface with the lower pressure on the powder flow path side of the boundary surface. When the pressure rise is created powder flowing through the valve is inhibited from adhering to the boundary surface or forming a stable arch. This technique of preventing powder sticking to a surface is already known per se but its use in a valve according to the invention is original.
  • According to another aspect of the invention there is provided a method of controlling the flow of a powder in which a portion of the path along which powder flows is surrounded by a perforated boundary surface and powder flow is stopped by creating a drop in pressure across the boundary surface with the higher pressure on the powder flow path side of the boundary surface.
  • By way of example a powder flow control valve embodying the invention will be described with reference to the accompanying drawing which is a side sectional view of the valve.
  • The control valve 1 is sited at the bottom of a shaft 2 of circular cross-section and includes a frusto-­conical part 3 made of porous plastics material which in this particular example is that sold by Porvair Ltd. under the trademark VYON. Immediately below the frusto-conical part 3 is a cylindrical part 4 leading to an outlet 5 of the valve. A plenum chamber 6 is defined between the outside of the frusto-conical part 3 and the walls of the shaft 2. The plenum chamber 6 is connected to a pumping system when can be arranged to suck air out of, or force air into, the chamber 6. The pumping system comprises a duct 11 which is connected, on the one hand, via a duct 7 and a valve 8 to a reservoir 9 of low pressure air maintained at low pressure by a pump 10 and, on the other hand, via a duct 12 and a valve 13 to a compressed air cylinder 14.
  • In use, powder is supplied to the top of the shaft 2 and falls down the shaft. When the valve 8 is open and the valve 13 closed, air is sucked out of the plenum chamber 6 and into the reservoir 9. Consequently, air is caused to flow from the shaft through the frusto-­conical part 3 into the chamber 6 and this causes powder to adhere to the surface of the part 3 and no powder reaches the outlet 5; this situation corresponds to the "closed" state of the valve. If, on the other hand, the valve 8 is closed and the valve 13 opened then air is blown into the plenum chamber 6 from the cylinder 14, the air flow through the part 3 is reversed and powder is prevented from sticking to the part 3 and falls through the outlet 5; this situation corresponds to the "open" state of the valve.
  • The valve 1 can therefore be used very effec­tively to control powder flow.
  • One particular example of a valve and powder that have been used successfully together will now be des­cribed. In this example the shaft 2 had an internal diameter d of 60 mm, the frusto-conical part 3 had a height h of 42 mm and a minimum internal diameter d₂ of 15 mm. The inclination α of the frusto-conical boundary surface to the horizontal was 60°. The powder used was agglomerated coffee which when subjected to a sieve analysis gave the results shown in the table below:
    Figure imgb0001
  • The porous material defining the boundary surface had a mean pore size of 70 microns and a thickness of 4.75 mm. The thickness is not however believed to be particularly significant. The porous material allowed a flow of air of 3.5 cm³/m²/min at a pressure of 3 kN/m².
  • In the "closed" state of the valve, the pressure in the plenum chamber 6 was 15" Hg (about 51 kN/m²) be­low atmospheric pressure and there was an air flow rate of 48 litres per minute (at atmospheric pressure). In the "open" state of the valve, the pressure in the plenum chamber was 6 psi (about 41 kN/m²) above atmospheric pressure and there was an air flow rate of 47 litres per minute (at atmospheric pressure).
  • The same valve was also tested with powdered milk and proved entirely satisfactory. Nonetheless it should be understood that the dimensions of the valve may need to be altered for different powders and in particular the dimensions d₂ may need to be varied. It is also possible to omit the cylindrical part 4 at the outlet of the valve without affecting the operation of the valve.
  • Tests have also been performed on powdered coffee, freeze dried coffee, household salt, granulated salt, coffee creamer, talc and flour and the valve of the invention has proved able to handle all these materials.
  • While in the described embodiments of the valve, the boundary surface is frusto-conical, other shapes of boundary surface could be employed. For example a surface of inverted pyramid shape could be used, or even a cylindrical shape.
  • Although the valve has been described almost exclusively in relation to controlling the flow of food powders it will be understood that applications of the valve may also be found outside the food industry.

Claims (20)

1. A powder flow control valve in which a powder flow path is surrounded by a perforated boundary surface and means are provided for creating a drop in pressure across the boundary surface with the higher pressure on the powder flow path side of the boundary surface.
2. A valve as claimed in claim 1 in which the means for creating a drop in pressure across the boundary sur­face operates by reducing the pressure on the opposite side of the boundary surface to the powder flow path without reducing, or without reducing so much, the pressure along the powder flow path.
3. A valve as claimed in claim 1 or 2 in which the cross-sectional area of the flow path surrounded by the perforated boundary surface decreases in the downstream direction.
4. A valve as claimed in any preceding claim in which the boundary surface has rotational symmetry.
5. A valve as claimed in claim 4 in which the boundary surface includes a substantially frusto-conical portion with the smaller diameter portion downstream of the larger diameter portion.
6. A valve as claimed in any preceding claim in which the portion of the powder flow path surrounded by the perforated boundary surface is substantially vertical.
7. A valve as claimed in any preceding claim in which the perforated boundary surface is made of a porous material.
8. A valve as claimed in any of claims 1 to 6 in which the perforated boundary surface is provided by a component with apertures formed therein at a multipli­city of predetermined locations.
9. A valve as claimed in claim 8 in which the locations are evenly distributed around the boundary surface.
10. A valve as claimed in any preceding claim further including means for creating a pressure rise across the boundary surface with the lower pressure on the powder flow path side of the boundary surface.
11. A method of controlling the flow of a powder in which a portion of the path along which powder flows is surrounded by a perforated boundary surface and powder flow is stopped by creating a drop in pressure across the boundary surface with the higher pressure on the powder flow path side of the boundary surface.
12. A method as claimed in claim 11 in which the drop in pressure is created by reducing the pressure on the opposite side of the boundary surface to the powder flow path without reducing, or without reducing so much, the pressure along the powder flow path.
13. A method as claimed in claim 11 or 12 in which the cross-sectional area of the flow path surrounded by the perforated boundary surface decreases in the down­stream direction.
14. A method as claimed in any of claims 11 to 13 in which the boundary surface has rotational symmetry.
15. A method as claimed in claim 14 in which the boundary surface includes a substantially frusto-conical portion with the smaller diameter portion downstream of the larger diameter portion.
16. A method as claimed in claim 14 or 15 in which the portion of the powder flow path surrounded by the perforated boundary surface is substantially vertical.
17. A method as claimed in any of claims 11 to 16 in which the perforated boundary surface is made of a porous material.
18. A method as claimed in any of claims 11 to 17 in which the perforated boundary surface is provided by a component with apertures formed therein at a multipli­city of predetermined locations.
19. A method as claimed in claim 18 in which the locations are evenly distributed around the boundary surface.
20. A method as claimed in any of claims 11 to 19 further including the step of creating a pressure rise across the boundary surface with the lower pressure on the powder flow path side of the boundary surface.
EP85308409A 1984-05-18 1985-11-19 Powder flow control valve Withdrawn EP0224621A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB08412802A GB2158813B (en) 1984-05-18 1984-05-18 Powder flow control valve
EP85308409A EP0224621A1 (en) 1985-11-19 1985-11-19 Powder flow control valve

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP85308409A EP0224621A1 (en) 1985-11-19 1985-11-19 Powder flow control valve

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EP0224621A1 true EP0224621A1 (en) 1987-06-10

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0318247A1 (en) * 1987-11-23 1989-05-31 G.E.I. Filling, Capping And Labelling Limited Powder flow control valves
WO1991017940A1 (en) * 1989-05-09 1991-11-28 Carl Edelmann Gmbh Worm drive metering device
US5405647A (en) * 1993-11-02 1995-04-11 Owens-Corning Fiberglass Technology Inc. Method for applying granules to a moving coated asphalt sheet to form areas having sharp leading and trailing edges
US5520889A (en) * 1993-11-02 1996-05-28 Owens-Corning Fiberglas Technology, Inc. Method for controlling the discharge of granules from a nozzle onto a coated sheet
US5599581A (en) * 1993-11-02 1997-02-04 Owens Corning Fiberglas Technology, Inc. Method for pneumatically controlling discharge of particulate material
US5624522A (en) * 1995-06-07 1997-04-29 Owens-Corning Fiberglas Technology Inc. Method for applying granules to strip asphaltic roofing material to form variegated shingles
US5747105A (en) 1996-04-30 1998-05-05 Owens Corning Fiberglas Technology Inc. Traversing nozzle for applying granules to an asphalt coated sheet
US5746830A (en) * 1993-11-02 1998-05-05 Owens-Corning Fiberglas Technology, Inc. Pneumatic granule blender for asphalt shingles
WO1999041148A1 (en) * 1998-02-11 1999-08-19 Robert Bosch Gmbh Metering device for pourable goods
WO2010149133A1 (en) * 2009-06-22 2010-12-29 Voxeljet Technology Gmbh Method and device for switching a particulate material flow in the construction of models in layers
US8956140B2 (en) 2010-07-13 2015-02-17 Voxeljet Ag Apparatus for producing three-dimensional models by means of a layer build up technique
US9242413B2 (en) 2011-01-05 2016-01-26 Voxeljet Ag Device and method for constructing a laminar body comprising at least one position adjustable body defining the working area
US10442170B2 (en) 2013-12-20 2019-10-15 Voxeljet Ag Device, special paper, and method for producing shaped articles
IT201900003497A1 (en) * 2019-03-11 2020-09-11 System Ceramics S P A POWDER DISPENSER DEVICE
WO2022097027A1 (en) * 2020-11-06 2022-05-12 System Ceramics S.P.A. Dispensing device for granular and/or powdered materials

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB422699A (en) * 1933-06-13 1935-01-14 Int Cigar Mach Co Mechanism for removing dust and the like from tobacco and other materials
US3305276A (en) * 1965-04-08 1967-02-21 Buehler Ag Geb Silo construction
US4067623A (en) * 1974-04-02 1978-01-10 Polysius Ag Pneumatic pressure conveyor for fine material
EP0125585A1 (en) * 1983-05-11 1984-11-21 Erkomat Oy Equipment for the removal of air out of pulverulent materials
GB2158813A (en) * 1984-05-18 1985-11-20 Loughborough Consult Ltd Powder flow control valve

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB422699A (en) * 1933-06-13 1935-01-14 Int Cigar Mach Co Mechanism for removing dust and the like from tobacco and other materials
US3305276A (en) * 1965-04-08 1967-02-21 Buehler Ag Geb Silo construction
US4067623A (en) * 1974-04-02 1978-01-10 Polysius Ag Pneumatic pressure conveyor for fine material
EP0125585A1 (en) * 1983-05-11 1984-11-21 Erkomat Oy Equipment for the removal of air out of pulverulent materials
GB2158813A (en) * 1984-05-18 1985-11-20 Loughborough Consult Ltd Powder flow control valve

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0318247A1 (en) * 1987-11-23 1989-05-31 G.E.I. Filling, Capping And Labelling Limited Powder flow control valves
GB2212790A (en) * 1987-11-23 1989-08-02 Portals Eng Ltd Improvements in or relating to flow control valves
US4974646A (en) * 1987-11-23 1990-12-04 Portals Engineering Limited Powder flow control valve
GB2212790B (en) * 1987-11-23 1992-01-08 Portals Eng Ltd Improvements in or relating to powder flow control valves
WO1991017940A1 (en) * 1989-05-09 1991-11-28 Carl Edelmann Gmbh Worm drive metering device
US5405647A (en) * 1993-11-02 1995-04-11 Owens-Corning Fiberglass Technology Inc. Method for applying granules to a moving coated asphalt sheet to form areas having sharp leading and trailing edges
US5520889A (en) * 1993-11-02 1996-05-28 Owens-Corning Fiberglas Technology, Inc. Method for controlling the discharge of granules from a nozzle onto a coated sheet
US5599581A (en) * 1993-11-02 1997-02-04 Owens Corning Fiberglas Technology, Inc. Method for pneumatically controlling discharge of particulate material
US5746830A (en) * 1993-11-02 1998-05-05 Owens-Corning Fiberglas Technology, Inc. Pneumatic granule blender for asphalt shingles
US5624522A (en) * 1995-06-07 1997-04-29 Owens-Corning Fiberglas Technology Inc. Method for applying granules to strip asphaltic roofing material to form variegated shingles
US5747105A (en) 1996-04-30 1998-05-05 Owens Corning Fiberglas Technology Inc. Traversing nozzle for applying granules to an asphalt coated sheet
WO1999041148A1 (en) * 1998-02-11 1999-08-19 Robert Bosch Gmbh Metering device for pourable goods
WO2010149133A1 (en) * 2009-06-22 2010-12-29 Voxeljet Technology Gmbh Method and device for switching a particulate material flow in the construction of models in layers
US9174392B2 (en) 2009-06-22 2015-11-03 Voxeljet Ag Method and device for switching a particulate material flow in the construction of models in layers
US9931762B2 (en) 2009-06-22 2018-04-03 Voxeljet Ag Method and device for switching a particulate material flow in the construction of models in layers
US9149987B2 (en) 2010-07-13 2015-10-06 Voxeljet Ag Device for producing three-dimensional models by a layering technique
US8956140B2 (en) 2010-07-13 2015-02-17 Voxeljet Ag Apparatus for producing three-dimensional models by means of a layer build up technique
US10946636B2 (en) 2011-01-05 2021-03-16 Voxeljet Ag Device and method for constructing a layer body
US9242413B2 (en) 2011-01-05 2016-01-26 Voxeljet Ag Device and method for constructing a laminar body comprising at least one position adjustable body defining the working area
US9649812B2 (en) 2011-01-05 2017-05-16 Voxeljet Ag Device and method for constructing a laminar body comprising at least one position-adjustable body defining the working area
US10513105B2 (en) 2011-01-05 2019-12-24 Voxeljet Ag Device and method for constructing a layer body
US11407216B2 (en) 2011-01-05 2022-08-09 Voxeljet Ag Device and method for constructing a layer body
US10442170B2 (en) 2013-12-20 2019-10-15 Voxeljet Ag Device, special paper, and method for producing shaped articles
US10889055B2 (en) 2013-12-20 2021-01-12 Voxeljet Ag Device, special paper, and method for producing shaped articles
WO2020183353A1 (en) * 2019-03-11 2020-09-17 System Ceramics S.P.A. Distributing device for powder materials
IT201900003497A1 (en) * 2019-03-11 2020-09-11 System Ceramics S P A POWDER DISPENSER DEVICE
WO2022097027A1 (en) * 2020-11-06 2022-05-12 System Ceramics S.P.A. Dispensing device for granular and/or powdered materials

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