EP1613455A1 - Appareil pour le traitement thermique de feuilles plastiques obtenues en continu - Google Patents

Appareil pour le traitement thermique de feuilles plastiques obtenues en continu

Info

Publication number
EP1613455A1
EP1613455A1 EP04721252A EP04721252A EP1613455A1 EP 1613455 A1 EP1613455 A1 EP 1613455A1 EP 04721252 A EP04721252 A EP 04721252A EP 04721252 A EP04721252 A EP 04721252A EP 1613455 A1 EP1613455 A1 EP 1613455A1
Authority
EP
European Patent Office
Prior art keywords
sheet
treatment stage
stage
heating
treatment
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Withdrawn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
EP04721252A
Other languages
German (de)
English (en)
Inventor
Giorgio Gatti
Gaspare Tacchi
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.)
Amut SpA
Original Assignee
Amut SpA
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 Amut SpA filed Critical Amut SpA
Publication of EP1613455A1 publication Critical patent/EP1613455A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B13/00—Conditioning or physical treatment of the material to be shaped
    • B29B13/02—Conditioning or physical treatment of the material to be shaped by heating
    • B29B13/023—Half-products, e.g. films, plates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C51/00—Shaping by thermoforming, i.e. shaping sheets or sheet like preforms after heating, e.g. shaping sheets in matched moulds or by deep-drawing; Apparatus therefor
    • B29C51/26—Component parts, details or accessories; Auxiliary operations
    • B29C51/42—Heating or cooling
    • B29C51/421—Heating or cooling of preforms, specially adapted for thermoforming
    • B29C51/424—Heating or cooling of preforms, specially adapted for thermoforming using a heated fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
    • B29C35/02—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould
    • B29C35/04—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould using liquids, gas or steam
    • B29C35/045—Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mould using liquids, gas or steam using gas or flames
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2021/00—Use of unspecified rubbers as moulding material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/25—Solid
    • B29K2105/253—Preform
    • B29K2105/256—Sheets, plates, blanks or films

Definitions

  • the present invention relates to a device for the thermal treatment of plastic material and, in particular, a device for performing the preheating of a continuous sheet of thermoformable plastic material before the sheet reaches the forming station.
  • EP-A-508.069 Another example of a prior art device can be found in European patent application no. EP-A-508.069, in which the sheet passes in a chamber resting on rows of upper and lower rollers, so as to form vertical loops.
  • the continuous sheet heating is obtained only by introducing hot air forced inside the chamber.
  • the sheet motion may be performed only by traction through of a couple of counterposed rollers, at least one of which is motor-driven, positioned downstream , from the pathway of the sheet inside the chamber itself.
  • thermoforming station requires particular attention both with regards to the temperatures to which the sheet must be subjected and with regards to the movement of the same along the thermal treatment device.
  • thermoforming operations For example, an excessive instantaneous heating can give rise to modifications in the inner structure of the material and subsequently compromise the correct execution of the thermoforming operations. Another undesired effect may occur if the heated sheet is subjected to an excessive tensile force, which can cause the stretching of the material and thus waste in the subsequent production.
  • the thermal characteristics of certain thermoformable plastics are particularly critical and may also be considerably different from other equally useable materials. For example, the temperature range within which a material may be subjected to thermoforming may vary considerably from a few degrees (4-5 °C for polypropylene) to several tens of degrees (15-25 °C for polystyrene). It thus follows that the preventive thermal treatment of the plastic material is a particularly critical factor for the correct execution of the subsequent thermoforming operation.
  • the object of the present invention is that of providing a device for the thermal treatment for plastic material enabling to make the heating of the sheet material to be subjected to thermoforming particularly efficient and safe.
  • Another object of the present invention is that of providing a device of the abovementioned type in which damage to the material before the forming phase can be prevented.
  • a further object of the present invention is that of providing a device of the abovementioned type that can be easily and efficiently adapted to the trealmenl of plastic materials having different thermal characteristics.
  • the thermal treatment device comprises in the known way means for making the continuous sheet to pass through at least one treatment stage and heating means for heating the continuous sheet to at least one preset temperature.
  • the present invention proposes a thermal treatment device that provides, in relation to the transit direction of the sheet, at least one first treatment stage in which the sheet is heated to at least one first preset temperature and at least one second treatment stage in which the sheet is heated to at least one second preset temperature.
  • the sheet may thus be gradually heated in the first stage, taking it for example from the room temperature present outside the device to a first preset temperature, which will also be defined below as the conditioning temperature.
  • a first preset temperature which will also be defined below as the conditioning temperature.
  • the sheet is taken to a second temperature, higher than the first, without causing damage to the inner structure of the material.
  • the means for making the continuous sheet to pass through the treatment stages advantageously comprise at least one motor-driven traction unit arranged downstream from the second stage and at least one braking unit arranged upstream from the first stage.
  • the traction and braking units are preferably activated under the control of suitable means that regulate the feeding speed and/or traction of the sheet during the transit of the first two treatment stages.
  • suitable means that regulate the feeding speed and/or traction of the sheet during the transit of the first two treatment stages.
  • the feeding speed of the sheet and the traction exerted on the same are preferably maintained constant. In this way undesired material stretching can be avoided.
  • the heating of the sheet is made by means of hot air circulation in the first stage and by means of heating plates in the second stage.
  • Heating temperature control is performed by suitable control means on the basis of signals received from temperature detecting sensors along the pathway of the sheet.
  • the device according to the invention advantageously also provides a third treatment stage, which is thermally insulated in relation to the outside environment and in relation to the first two stages positioned upstream.
  • a third treatment stage which can be free of heating means and motor-driven means, a sufficient amount of sheet, or in any case an amount greater than that required to feed the thermoforming machine, positioned downstream for at least one forming cycle is kept.
  • the stabilisation stage the heat accumulated in the previous treatment stages can thus be distributed homogeneously on the entire sheet before being withdrawn by the thermoforming machine.
  • thermoforming cycle the time of permanence of the sheet in the various treatment stages can be set in a particularly efficient and effective way, and the most suitable temperatures for the different types of material can be subsequently subjected to forming.
  • FIG 1 is a schematic representation of a thermal treatment device according to the present invention
  • Figure 2 is a cross-section view of a detail of the thermal treatment device according to one possible embodiment of the present invention.
  • FIG. 3 is a longitudinal section view of another detail of the thermal treatment device according to one possible embodiment of the present invention, Modes for Carrying Out the Invention
  • the device comprises a chamber 10 defined by a casing 1 1 in thermoinsulating material.
  • the continuous sheet 1 of thermoformable plastic material is withdrawn from a reel (not shown) positioned upstream from the device and made to pass inside the device, with a movement in the direction of the arrow P, through an inlet aperture 12.
  • the pathway of the sheet 1 inside the chamber 10 is made around a plurality of idle rollers 15 partially arranged along two counterposed rows on the upper part and the lower part of the chamber 10 respectively, which give to the sheet 1 a vertical loop layout in the zone being the first thermal treatment stage 100.
  • 1 is made by the circulation of hot air introduced into the chamber 10 through a port 50.
  • One or more temperature sensors 51 are arranged in suitable positions in the chamber 10 in order to detect the temperature of the air circulating in the chamber itself.
  • the sheet 1 is then made to pass through a second thermal treatment stage 200 contained inside the chamber 10 and optionally heat insulated in relation to the same, if necessary by a shell 21 (represented with dotted line) in ⁇ thermally insulating material.
  • the heating of the sheet 1 in the second thermal treatment stage 200 is made by two electrically driven heating plates 22 facing each of 1he two sides of the sheet 1.
  • the sheet 1 is heated to a higher temperature than the first stage 100.
  • Control means receiving the signals provided by the temperature sensors 51 are suitably provided and enable to set and maintain the temperatures desired in each of the two stages depending on the material used.
  • a traction unit 30 arranged downstream of the second stage 200 and a braking unit 40 arranged upstream of the first stage 100 are provided.
  • the traction unit 30 is driven by an electric motor 31 that makes at least one of the two coupled rollers 35 rotate.
  • the braking unit 40 is made up in turn by two coupled rollers 45, at least one of which is subject to braking, for example by a pincer mechanism that can be activated manually or pneumatically.
  • the rollers 45 may also be connected to an electric motor suitably activated with torque and speed values such as to ensure the correct tensioning of the sheet 1.
  • the activation of the traction 30 and braking 40 unit is performed under the control of suitable means able to set and maintain constant transfer speed, so as to control and maintain substantially constant the tension to which the sheet 1 is subjected while transiting inside the device.
  • the development of the pathway of the sheet 1 through the first stage 100 is greater than that in the second stage 200.
  • the first stage 100 also defined as accumulation or conditioning stage
  • the overall development of the sheet 1 around the idle rollers 15, in the same way as the setting of the constant towing speed enables to determine the permanence time of the sheet 1 in the first treatment stage 100.
  • the second treatment stage 200 also defined as the heating stage, the sheet 1 is heated on both faces to a higher preset temperature than that of the first stage 100.
  • the device further comprises a third stage 300 separated from the first two and formed inside a chamber 60 defined by a casing 61 in thermally insulating material.
  • the heating means may also not be provided.
  • the heat accumulated previously by the sheet 1 is evenly distributed before a certain amount thereof is withdrawn by the thermoforming machine which is arranged immediately downstream.
  • the sheet 1 forms a loop 2 between an idle roller 65 and a guide element 66 that takes the sheet 1 towards the outlet aperture 62.
  • the guide element 66 consisting of for example a suitable shaped plate, has associated an idle roller 67 that keeps the sheet 1 in close contact to the same guide element 66.
  • the loop 2 formed in the chamber 60 is a store of material that advantageously enables to maintain a constant speed motion of the sheet 1 in the thermal treatment device despite the alternate motion of the thermoforming machine positioned upstream of the device itself.
  • the withdrawal of the sheet 1 through the outlet aperture 62 is made by the same thermoforming machine and therefore during the treatment stage no motor-driven moving means of the sheet 1 are provided.
  • FIGS 2 and 3 illustrate a number of details of the heating means used in the device according to the present invention.
  • FIG. 2 illustrates an assembly 70 for making the circulation of hot air in the chamber 10 through the casing 1 1.
  • the assembly 70 essentially comprises a blower 71 driven by an electric motor 72 and an electrical heating unit 73.
  • the activation of the motor 72 and of the heating unit 73 is subjected to the control of the previously mentioned control means on the basis of the signals received from the temperature sensors 51 ( Figure 1 ).
  • the hot air flow it thus conveyed into the chamber 10 by a pipe fitted into the port 50 and distributed inside the chamber itself by one or more diffuser elements 75.
  • FIG. 3 illustrates in greater detail the heating plates 22 provided in the second thermal treatment stage 200.
  • the plates 22 are removably mounted on a frame 23, so as to aid the positioning of the sheet 1 before operating the device.
  • the plates 22 are electrically heated and can be, for example, of the induction- type heating, or any other type suitable to ensure the controlled heating of the sheet 1 during its passage between the plates themselves.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)

Abstract

L'invention porte sur un appareil de traitement thermique pour matières plastiques présentées sous forme de feuilles plastiques obtenues en continu. L'appareil comporte deux phases (100, 200, 300) de traitement thermique à différentes températures.
EP04721252A 2003-04-11 2004-03-17 Appareil pour le traitement thermique de feuilles plastiques obtenues en continu Withdrawn EP1613455A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITMI20030768 ITMI20030768A1 (it) 2003-04-11 2003-04-11 Dispositivo per il trattamento termico di materiale plastico.
PCT/IB2004/000774 WO2004089589A1 (fr) 2003-04-11 2004-03-17 Appareil pour le traitement thermique de feuilles plastiques obtenues en continu

Publications (1)

Publication Number Publication Date
EP1613455A1 true EP1613455A1 (fr) 2006-01-11

Family

ID=33156351

Family Applications (1)

Application Number Title Priority Date Filing Date
EP04721252A Withdrawn EP1613455A1 (fr) 2003-04-11 2004-03-17 Appareil pour le traitement thermique de feuilles plastiques obtenues en continu

Country Status (3)

Country Link
EP (1) EP1613455A1 (fr)
IT (1) ITMI20030768A1 (fr)
WO (1) WO2004089589A1 (fr)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5324642B2 (ja) 2008-03-25 2013-10-23 スリーエム イノベイティブ プロパティズ カンパニー 塗装フィルム複合体及びその製造方法
BRPI0909077A2 (pt) 2008-03-25 2015-08-25 3M Innovative Properties Co Artigos multicamadas e métodos de preparo e uso dos mesmos
IT1401331B1 (it) * 2010-08-02 2013-07-18 Sarong Spa Stazione di riscaldamento
IT1401330B1 (it) * 2010-08-02 2013-07-18 Sarong Spa Stazione di riscaldamento
IT1401328B1 (it) * 2010-08-02 2013-07-18 Sarong Spa Apparato di formatura
IT1401329B1 (it) * 2010-08-02 2013-07-18 Sarong Spa Stazione e metodo di riscaldamento
CN105082519B (zh) * 2010-08-02 2018-11-02 萨龙股份公司 加热方法
ITMI20110845A1 (it) * 2011-05-13 2012-11-14 Termostampi S R L Impianto di termoformatura a rigenerazione di calore e relativo procedimento
DE102017005531A1 (de) * 2017-06-10 2018-12-27 Illig Maschinenbau Gmbh & Co. Kg Heizeinrichtung für eine Thermoformmaschine

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2055733T3 (es) * 1987-06-23 1994-09-01 Shionogi & Co Metodo y aparato para la formacion de bolsas de ptp.
US5125994A (en) * 1989-11-01 1992-06-30 Eastman Kodak Company Thermoforming method
DE4104461A1 (de) * 1991-02-14 1992-08-20 Illig Maschinenbau Adolf Heizeinrichtung zum beheizen von thermoplastischer kunststoffolie
DE4111315A1 (de) * 1991-04-08 1992-10-15 Kiefel Gmbh Paul Vorrichtung zum vorwaermen von kunststoffolien
DE9304203U1 (de) * 1993-03-20 1993-06-03 Hemmerle Maschinen- und Werkzeugbau, 88459 Tannheim Vorrichtung zum Erwärmen von Tiefziehfolien
US5423669A (en) * 1993-08-19 1995-06-13 Chapman; Michael Apparatus for thermoforming shaped articles

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2004089589A1 *

Also Published As

Publication number Publication date
WO2004089589A1 (fr) 2004-10-21
ITMI20030768A1 (it) 2004-10-12

Similar Documents

Publication Publication Date Title
WO2004089589A1 (fr) Appareil pour le traitement thermique de feuilles plastiques obtenues en continu
EP2972035B1 (fr) Four de séchage de bois à passages multiples
WO2012017352A1 (fr) Appareil de formage, poste de chauffage et procédé permettant de chauffer des parties définies
US4520575A (en) Impingement oven and method
CN206583311U (zh) 热风预热装置
US4935077A (en) Process for bonding cellulosic nonwovens with thermoplastic fibers using infrared radiation
CN116576653A (zh) 一种无纺布烘箱及其保护机构
WO2003029546A1 (fr) Rameuse
CN211903636U (zh) 一种加热均匀的地毯烘干装置
JP3066747B1 (ja) 加流装置
CN210832950U (zh) 一种多功能层烘干固化设备
CZ20002793A3 (cs) Způsob přípravy zesítěných polyolefinových pěn a zařízení k jeho provádění
US7101500B2 (en) Method for creating a substantially uniform temperature across a plastic sheet for delivery to an appliance liner thermoforming device
CN115094598B (zh) 一种辐射式体积恢复装置
TWI806557B (zh) 片狀物之加熱乾燥裝置
EP1841588B1 (fr) Appareil a stabiliser le traitement thermique de bandes de plastique, notamment de polypropylene et/ou de polyethylene, pour la production de brides ou d'autres types de bandes
RU2382305C1 (ru) Устройство для охлаждения и сушки изделий
JPS6014567Y2 (ja) 熱可塑性樹脂シ−ト成形機の加熱装置
TWI744722B (zh) 用於移動中腹板材之熱處理的裝置及方法
JP2007519536A (ja) 印刷版炉における及び関する改良
KR102170724B1 (ko) 에어컨 배관 보온재 제조장치 및 그 제조방법
US1860411A (en) Apparatus and process for vulcanizing rubber coated fabric
KR20150062431A (ko) 진공단열재의 단열심재 건조장치
US20140070450A1 (en) Continuous curing and post-curing method
JP2983270B2 (ja) 延伸機

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20051024

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20060523