EP0564013A1 - Procédé pour proportionner des composants de colle - Google Patents

Procédé pour proportionner des composants de colle Download PDF

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Publication number
EP0564013A1
EP0564013A1 EP93200571A EP93200571A EP0564013A1 EP 0564013 A1 EP0564013 A1 EP 0564013A1 EP 93200571 A EP93200571 A EP 93200571A EP 93200571 A EP93200571 A EP 93200571A EP 0564013 A1 EP0564013 A1 EP 0564013A1
Authority
EP
European Patent Office
Prior art keywords
components
storage containers
time
mixing ratio
weight per
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.)
Granted
Application number
EP93200571A
Other languages
German (de)
English (en)
Other versions
EP0564013B1 (fr
Inventor
Lennart Vesterlund
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.)
Casco Products AB
Original Assignee
Casco Nobel AB
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
Application filed by Casco Nobel AB filed Critical Casco Nobel AB
Publication of EP0564013A1 publication Critical patent/EP0564013A1/fr
Application granted granted Critical
Publication of EP0564013B1 publication Critical patent/EP0564013B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B01F35/80—Forming a predetermined ratio of the substances to be mixed
    • B01F35/83—Forming a predetermined ratio of the substances to be mixed by controlling the ratio of two or more flows, e.g. using flow sensing or flow controlling devices
    • B01F35/832—Flow control by weighing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/40—Mixing liquids with liquids; Emulsifying

Definitions

  • the invention relates to a method for mixing binders using at least two components, which are flowed from separate storage containers towards a common mixing point.
  • the storage containers are continuously weighed, and their change of weight per unit of time is determined.
  • the invention concerns a device for implementing the method.
  • the resin and the curing agent When using curing adhesive systems, the resin and the curing agent must be kept in separate containers and should not be mixed until a short time before applying the glue. If the glue line is to be sufficiently strong, the mixing ratio of resin to curing agent has to be precise. This is especially important in the making of load-bearing constructions, such as beams, where a weak glue line may have disastrous consequences.
  • the invention concerns a method for mixing binders using at least two components including a resin and a curing agent, which are flowed from separate storage containers towards a common mixing point.
  • the storage containers are continuously weighed, and their change of weight per unit of time is determined.
  • the flow ratio, and consequently also the actual mixing ratio of the components can be determined on the basis of the change of weight per unit of time of each container.
  • the measured and/or determined values are stored in a form which enables subsequent control of the mixing ratio between the components at a certain point of time.
  • the data may, for instance, be stored in a memory in the control unit, in other machine-readable form, or be printed directly on a paper.
  • the control unit may also permit direct reading of all data on a display.
  • the actual mixing ratio is compared with a set point determined according to the binder system used. If the deviation exceeds a predetermined value, for instance ranging from about 0.5% to about 10% depending on the binder system, an alarm can be given, calling the attention of an operator who can then correct the deviation by altering the flow of one or more of the components, e.g. by changing the speed of one or more of the dosing pumps.
  • the determination of the actual mixing ratio and the comparison with the set point are automatically performed in a control unit, which also makes it possible to allow the control unit to automatically control the flow of one or more of the components on the basis of the measured changes of weight per unit of time of each storage container, thereby substantially maintaining a set point for the mixing ratio of the components. If the components are a resin and a curing agent, it is generally sufficient that the control unit automatically controls the speed of one dosing pump for the curing agent.
  • the storage containers are weighed on scales transmitting signals to the control unit, which can be done e.g. by suspending the containers from preferably electronic load transducers.
  • the load transducers should be able to yield such accurate weighing results that the deviation is at the most about ⁇ 5%, in particular at the most ⁇ about 2%.
  • the method according to the invention is advantageous for all curing binder systems in which two or more components are to be mixed, for instance resorcinol-formaldehyde resin and formaldehyde curing agent, or urea resin and an acid curing agent, such as ammonium chloride.
  • a resin and an acid curing agent such as ammonium chloride.
  • other common additives to binders such as diluents (e.g. water or organic solvents), fillers and plasticisers, can be admixed to the binder in the same way.
  • the components can be brought together and mixed by known methods, e.g. in closed vessels; on a plate, as in SE Patent 418,753; on a roller, as in SE Patent Application 9102874-6; or on the object to be coated with the binder, as in SE Patent 373,525.
  • the invention further concerns a device for implementing the method.
  • This device comprises separate storage containers and dosing pumps for each component, means for continuously weighing each storage container, and means for determining the change of weight of the storage containers per unit of time.
  • the storage containers are suspended from preferably electronic load transducers transmitting signals to a control unit capable of determining the change of weight per unit of time for each storage container.
  • the control unit is adapted to determine the actual mixing ratio of the components, compare this ratio with a set point, and give an alarm if the deviation exceeds a predetermined value.
  • control unit is adapted to automatically control the flow of one or more of the components on the basis of the measured changes of weight per unit of time of the storage container of each component, thereby substantially maintaining a set point for the mixing ratio of the components.
  • the device comprises means for storing the measured and/or determined values in a form enabling subsequent control of the mixing ratio between the components at a certain point of time.
  • the invention there is no need of continuous manual supervision for immediately detecting and adjusting deviations in the mixing ratio of resin to curing agent that may arise owing to alterations of the viscosity, clogging of the equipment, leakage, or quite simply by the emptying of a storage container.
  • it is possible to accurately control the mixing ratio of resin to curing agent, which is a condition for obtaining glue lines of high and uniform quality.
  • the invention also makes it possible to control the total consumption of the binder and thereby optimise this amount.
  • the drawing shows two storage tanks 1, 2 for resin and curing agent, respectively.
  • dosing pumps 6, 7 which lead to a common mixing point (not shown).
  • the tanks 1, 2 are suspended from electronic load transducers 3, 4 which are connected to a control unit 5.
  • the control unit 5 is adapted to control one or both of the dosing pumps 6, 7.
  • the tanks 1, 2 contain liquid resin and liquid curing agent, respectively. Resin and curing agent are pumped to a common mixing point by the dosing pumps 6, 7. A suitable mixing ratio of resin to curing agent, e.g. ranging from about 1:1 to about 1:100 depending on the adhesive system and the degree of dilution, is set on the control unit 5 and then constitutes a set point.
  • the electronic load transducers 3, 4 continuously transmit signals relating to the weight of the tanks 1, 2, to the control unit 5 which, at suitable time intervals, e.g. ranging from about 1 second to 5 minutes, records the weight and compares it with the preceding value, thereby determining the loss of weight of each tank 1, 2 per unit of time.
  • the actual mixing ratio of resin to curing agent is determined.
  • the measured and the determined values of the flow and the mixing ratio of the resin and the curing agent is stored in the control unit 5, and/or transmitted to a printer (not shown), thus enabling subsequent control of the actual mixing ratio at a certain point of time.
  • an alarm is given, calling the attention of an operator who may then check whether there is any serious malfunction, and optionally adjust the speed of e.g. the dosing pump for the curing agent, thereby establishing a suitable mixing ratio once again.
  • one or both of the dosing pumps 6, 7 are automatically controlled by the control unit, so as to maintain at all times a correct mixing ratio. An alarm is given only when the disturbances are so severe that they cannot be offset by adjusting the dosing pumps 6, 7, e.g. if the flow is completely stopped by clogging or if one of the tanks has become empty.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Adhesives Or Adhesive Processes (AREA)
  • Accessories For Mixers (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Materials For Medical Uses (AREA)
  • External Artificial Organs (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Structure Of Belt Conveyors (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Die Bonding (AREA)
  • Dicing (AREA)
  • Organic Insulating Materials (AREA)
  • Detergent Compositions (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Coating Apparatus (AREA)
EP93200571A 1992-03-30 1993-03-02 Procédé pour proportionner des composants des adhésifs Expired - Lifetime EP0564013B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9200988 1992-03-30
SE9200988A SE9200988L (sv) 1992-03-30 1992-03-30 Sätt vid limning

Publications (2)

Publication Number Publication Date
EP0564013A1 true EP0564013A1 (fr) 1993-10-06
EP0564013B1 EP0564013B1 (fr) 1998-01-21

Family

ID=20385789

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93200571A Expired - Lifetime EP0564013B1 (fr) 1992-03-30 1993-03-02 Procédé pour proportionner des composants des adhésifs

Country Status (8)

Country Link
EP (1) EP0564013B1 (fr)
AT (1) ATE162426T1 (fr)
DE (1) DE69316420T2 (fr)
DK (1) DK0564013T3 (fr)
ES (1) ES2112380T3 (fr)
FI (1) FI102876B1 (fr)
NO (1) NO308542B1 (fr)
SE (1) SE9200988L (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6414312B1 (en) 1998-03-05 2002-07-02 Akzo Nobel N.V. Method for controlling a process for the production of a cellulose fiber containing product
EP2803425A1 (fr) * 2013-05-13 2014-11-19 Loramendi, S.COOP. Appareil de dosage et procédé de fonctionnement pour un appareil de dosage
CN106881049A (zh) * 2015-12-15 2017-06-23 上海奥星制药技术装备有限公司 均质控制系统及其控制方法
WO2020094529A1 (fr) * 2018-11-05 2020-05-14 Gurit (Uk) Ltd Appareil et procédé de commande du mélange de composants de systèmes de résine durcissable

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2925197A (en) * 1956-10-03 1960-02-16 Carl Schenck Machinenfabrik G Method of and apparatus for feeding liquid to flowing material
US3245584A (en) * 1964-05-20 1966-04-12 Richard D Linville Method and apparatus for mixing and blending
US3442453A (en) * 1965-04-30 1969-05-06 Ben Whitehouse Jr Dispensing unit
US3638916A (en) * 1970-09-01 1972-02-01 Phillips Petroleum Co Method and apparatus for blending materials
DE2152533A1 (de) * 1970-10-23 1972-04-27 List Heinz Verfahren zum kontinuierlichen Dosieren mehrerer Komponenten eines Mischproduktes und eine Vorrichtung zur Durchfuehrung dieses Verfahrens
US4525071A (en) * 1984-05-31 1985-06-25 Crawford & Russell, Inc. Additive inventory control, batching and delivery system
EP0170322A2 (fr) * 1984-07-31 1986-02-05 "National Forge Europe" Equipement pour mélanger des composants en forme de poudre et/ou de granules d'un corps devant être compressé sous haute pression
US4733971A (en) * 1986-02-26 1988-03-29 Micro Chemical, Inc. Programmable weight sensitive microingredient feed additive delivery system and method

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2925197A (en) * 1956-10-03 1960-02-16 Carl Schenck Machinenfabrik G Method of and apparatus for feeding liquid to flowing material
US3245584A (en) * 1964-05-20 1966-04-12 Richard D Linville Method and apparatus for mixing and blending
US3442453A (en) * 1965-04-30 1969-05-06 Ben Whitehouse Jr Dispensing unit
US3638916A (en) * 1970-09-01 1972-02-01 Phillips Petroleum Co Method and apparatus for blending materials
DE2152533A1 (de) * 1970-10-23 1972-04-27 List Heinz Verfahren zum kontinuierlichen Dosieren mehrerer Komponenten eines Mischproduktes und eine Vorrichtung zur Durchfuehrung dieses Verfahrens
US4525071A (en) * 1984-05-31 1985-06-25 Crawford & Russell, Inc. Additive inventory control, batching and delivery system
EP0170322A2 (fr) * 1984-07-31 1986-02-05 "National Forge Europe" Equipement pour mélanger des composants en forme de poudre et/ou de granules d'un corps devant être compressé sous haute pression
US4733971A (en) * 1986-02-26 1988-03-29 Micro Chemical, Inc. Programmable weight sensitive microingredient feed additive delivery system and method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6414312B1 (en) 1998-03-05 2002-07-02 Akzo Nobel N.V. Method for controlling a process for the production of a cellulose fiber containing product
EP2803425A1 (fr) * 2013-05-13 2014-11-19 Loramendi, S.COOP. Appareil de dosage et procédé de fonctionnement pour un appareil de dosage
WO2014184124A1 (fr) * 2013-05-13 2014-11-20 Loramendi, S.Coop. Appareil de dosage et procédé de fonctionnement d'un appareil de dosage
CN106881049A (zh) * 2015-12-15 2017-06-23 上海奥星制药技术装备有限公司 均质控制系统及其控制方法
WO2020094529A1 (fr) * 2018-11-05 2020-05-14 Gurit (Uk) Ltd Appareil et procédé de commande du mélange de composants de systèmes de résine durcissable
GB2578731B (en) * 2018-11-05 2023-05-10 Gurit Uk Ltd Apparatus for, and method of, controlling the mixing of components of curable resin systems

Also Published As

Publication number Publication date
FI102876B (fi) 1999-03-15
DE69316420T2 (de) 1998-06-25
EP0564013B1 (fr) 1998-01-21
FI931388L (fi) 1993-10-01
FI102876B1 (fi) 1999-03-15
ES2112380T3 (es) 1998-04-01
FI931388A0 (fi) 1993-03-26
ATE162426T1 (de) 1998-02-15
DE69316420D1 (de) 1998-02-26
NO931142L (no) 1993-10-01
SE9200988D0 (sv) 1992-03-30
NO308542B1 (no) 2000-09-25
NO931142D0 (no) 1993-03-26
SE9200988L (sv) 1993-10-01
DK0564013T3 (da) 1998-09-14

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