Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F11/00—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it
  • G01F11/02—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers which expand or contract during measurement
  • G01F11/021—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers which expand or contract during measurement of the piston type
  • G01F11/024—Apparatus requiring external operation adapted at each repeated and identical operation to measure and separate a predetermined volume of fluid or fluent solid material from a supply or container, without regard to weight, and to deliver it with measuring chambers which expand or contract during measurement of the piston type the pistons reciprocating in rotatable cylinders
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F13/00—Apparatus for measuring by volume and delivering fluids or fluent solid materials, not provided for in the preceding groups
  • G01F13/001—Apparatus for measuring by volume and delivering fluids or fluent solid materials, not provided for in the preceding groups for fluent solid material
  • G01F13/005—Apparatus for measuring by volume and delivering fluids or fluent solid materials, not provided for in the preceding groups for fluent solid material comprising a screw conveyor

Definitions

• the present invention relates to a volumetric dosing device that can be used, for example, for the dosing of liquid, pasty, particulate or powdered products, particularly in the food industry.
• These products include pasta, green beans, grains, rice, spinach, sauerkraut, chopped or shredded animal flesh, sliced potatoes, tabbouleh, celery remoulade, vinaigrette and other sauces ...
• Such a device is for example disposed between a hopper containing the bulk product and a container conveyor to be filled.
• FR-A-2,843,799 discloses a product dosing device comprising a fixed frame and a barrel which is rotatably mounted on the frame and which comprises a metering chamber having a transverse axis to the barrel to open laterally. outside the barrel on both sides of it.
• the barrel is mounted to pivot between a product inlet position in the metering chamber and a delivery position of the product out of the metering chamber.
• the metering device comprises means for introducing product into the metering chamber and delivering product out of the metering chamber.
• the introduction and discharge means comprise a suction piston and a discharge piston mounted on the frame to slide transversely to the barrel and enter the metering chamber when the barrel is in the corresponding positions so as to have a retracted position of the barrel and a position received in the metering chamber.
• This device effectively ensures accurate and fast dosing.
• the structure of this device is relatively complex and the achievement of a seal between the pistons and the chamber is delicate.
• DE-A-35 11 288 a product dosing device comprising a fixed frame and a barrel which is rotatably mounted on the frame and which comprises metering chambers having a transverse axis to the barrel for unclogging. laterally outside the barrel and in the center of it.
• a piston is mounted in each chamber to slide parallel to the axis of the chamber and carries a roller on a fixed cam extending in the center of the barrel.
• the cam has a profile arranged to move the pistons during the rotation of the barrel between two axially offset positions to achieve an admission of a predetermined amount of product and a discharge of the product so metered.
• the displacement of the piston is here inseparably linked to the rotation of the barrel.
• An object of the invention is to propose a dosing device which has a relatively simple structure and which is flexible in use while being precise.
• a product metering device comprising a fixed frame, at least one barrel which is rotatably mounted about an axis on the frame and which comprises at least one metering chamber having a axis transverse to the axis of rotation of the barrel and opening laterally outside the ring, a discharge piston being mounted in the metering chamber to slide parallel to the axis of the chamber.
• the piston is integral with a rack meshing with a pinion mounted on the barrel for pivoting about an axis parallel to the axis of rotation of the ring, means for driving the pinion in rotation. are connected to the frame and the device comprises means for maintaining the piston in a substantially constant position during rotation of the barrel.
• the movement of the piston is dissociated from the rotational movement of the barrel so that the parameters of these movements are independent.
• the pinion has a non-zero radius
• the point of contact of the pinion and the rack tends to move during the rotation of the barrel so that the rotation of the rack tends to cause a movement of the rack and therefore piston if the pinion remains fixed.
• the holding means prevent movement of the piston which would be detrimental to the accuracy of the assay and thus to maintain a precise dosage.
• the structure of the device is nevertheless relatively simple and easy to manufacture.
• the holding means are arranged to keep substantially constant the point of contact of the pinion and the rack and, in particular, to provide compensation for a relative movement of the pinion and the rack generated by the rotation of the barrel.
• the compensation of the relative movement of the pinion and the rack makes it possible to limit the influence of the rotation of the barrel on the position of the piston. This compensation can be obtained in a simple manner by appropriate control of the drive means for rotating the pinion.
• FIG. 1 is a partial schematic view in elevation and in section of a metering device according to the invention in a product packaging installation
• FIGS. 2 and 3 are cross-sectional views of this metering device in the start and end position
• 4 and 5 are cross-sectional views of the metering device in the start and end of discharge position.
• the packaging installation comprises a hopper 1, intended for the supply of product, having a bottom connected by a conduit 2 to a metering device, generally designated at 3, located opposite a portion of a container conveyor 4 each filled with a predetermined quantity of products.
• a metering device generally designated at 3 located opposite a portion of a container conveyor 4 each filled with a predetermined quantity of products.
• the metering device 3 comprises a frame 5, fixed, on which are mounted two rotating barrels 6 around an axis 7.
• the two barrels 6 are identical, superimposed and integral with each other.
• Each barrel 6 comprises a metering chamber 8 having an axis 9 (here diametrical) perpendicular to the axis 7 and opening out of the barrel 6 on either side thereof.
• the metering chamber 8 may have a rectangular, circular or other cross section.
• a piston 10 is mounted in the metering chamber 8 to slide parallel to the axis 9 between a first position flush with the outer surface of the barrel 6 and a second retracted position by a distance corresponding to the amount of product to be metered.
• the product is intended to be received in the metering chamber 8 on the side of the front face of the piston 10.
• the piston 10 has a part rear integral with a rack 11 extending parallel to the axis 9.
• the racks 11 mesh with a single pinion 12 mounted on the barrel 6 to pivot about an axis 13 parallel to the axis 7.
• the pinion 12 is integral with one end of a shaft 14 having an opposite end equipped with a pinion 15 meshing with the output pinion 16 of a servomotor 17 coaxial with the barrel 6.
• the barrels 6 are pivotally received in a enclosure 18 secured to the frame 5 and provided laterally with an inlet opening 19 and a discharge opening 20 disposed at the level of each metering chamber 8 facing respectively the conduit 2 and the conveyor 4.
• the barrel 6 is equipped with a toothed sector 21 on which meshes an output pinion of a servomotor 22 to drive the barrels 6 in rotation between an intake position in which the metering chamber 8 is opposite the intake opening 19 and a delivery position in which the metering chamber 8 is opposite the discharge opening 20.
• the two positions of the barrels 6 are therefore angularly offset relative to each other.
• the enclosure 18 is mounted on the frame 5 to pivot eccentrically about a vertical axis opposite the hopper 1 between a working position where the inlet openings 19 are opposite the conduit 2 and a position of cleaning in which the inlet openings 19 are clear of the conduit 2.
• the barrels 6 comprise, on the side of the rear face of the pistons, a flat forming a reserve 24 in which opens the metering chamber 8. This reserve is used during the liquid dosage. In the event of a piston leaking, the fluid passing from the rear side of the piston is received in the reserve 24 of so as not to exert a pressure behind the piston hindering the recoil movement of the piston.
• the barrels 6 are in the intake position and the pistons 10 are in the first position (FIG. 2).
• Supply screws 23 located at the bottom of the hopper are controlled to push the product into the conduit 2 and the metering chambers 8 while the servomotor 17 is controlled to drive the pinion 12 in rotation so as to bring the pistons 10 their first position to their second position ( Figure 3).
• the servomotor 22 is controlled to bring the barrels 6 into their delivery position and simultaneously the servomotor 17 is controlled to maintain the pistons 10 in their second position throughout the rotation of the barrels 6 ( Figure 4).
• the metering chambers 8 are closed off by the wall of the enclosure 18 which prevents the product from escaping.
• the servomotor 17 is controlled to move the pistons 10 to their first position (FIG. 5).
• the pistons 10 thus push the product out of the dosing chambers 8. Two doses of the product then fall into one of the containers to be filled.
• the sealing of the piston 10 can be carried out in such a way that the piston 10 draws the product into the metering chamber 8.
• the feed screws 23 to compress the product in the metering chambers 8.
• the invention is not limited to described embodiment and can be made variants without departing from the scope of the invention as defined by the claims.
• the pinion rotation drive means may be different from those described and may comprise a set of gears or a set of pulleys and belt interposed between the pinion and the motor, or a connected linear actuator. to a pinion drive rack.
• the holding means may have a different structure from that described and comprise a clutch disposed between the pinion 12 and the output gear 16 of the drive motor to let the pinion 12 free in rotation when the barrel rotates.
• a lost-stroke connection can be inserted between the rack and the piston to absorb the displacement of the rack during the rotation of the barrel (preferably, the device is arranged so that the rotation of the barrel from its suction position to its discharge position causes a movement of the rack forwardly).
• the metering device may have only one barrel or more than two barrels, the angular positions of the barrel may be shifted by an angle other than 90 °, the pivot axis of the barrel may be vertical. .
• the piston In its first position, the piston may extend projecting from the metering chamber 8 to, when the barrel is in the delivery position, be assured that the product does not remain hooked at the outlet of the dosing chamber.
• the means for introducing the product into the chambers may be different from the screws 23 and comprise, for example, a belt conveyor.
• the piston holding means may be arranged to allow a slight compression or expansion movement of the piston during the rotation of the barrel, in particular when the metering chamber is no longer opposite the intake opening.

Landscapes

• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• General Physics & Mathematics (AREA)
• Basic Packing Technique (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=35458008

Family Applications (1)

Country Status (4)

Families Citing this family (2)

Family Cites Families (5)

• 2005
  • 2005-04-20 FR FR0503945A patent/FR2884914B1/fr not_active Expired - Fee Related
• 2006
  • 2006-04-07 US US11/918,672 patent/US20090071984A1/en not_active Abandoned
  • 2006-04-07 WO PCT/FR2006/000772 patent/WO2006111629A1/fr not_active Ceased
  • 2006-04-07 EP EP06743655A patent/EP1872096A1/de not_active Withdrawn

Non-Patent Citations (1)

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