WO2010005279A1 - Corrugated board production belt lifting device - Google Patents

Corrugated board production belt lifting device Download PDF

Info

Publication number
WO2010005279A1
WO2010005279A1 PCT/MY2008/000166 MY2008000166W WO2010005279A1 WO 2010005279 A1 WO2010005279 A1 WO 2010005279A1 MY 2008000166 W MY2008000166 W MY 2008000166W WO 2010005279 A1 WO2010005279 A1 WO 2010005279A1
Authority
WO
WIPO (PCT)
Prior art keywords
corrugated board
conveyor belt
pair
board
rollers
Prior art date
Application number
PCT/MY2008/000166
Other languages
French (fr)
Inventor
Chee Meng Chan
Original Assignee
Chee Meng Chan
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 Chee Meng Chan filed Critical Chee Meng Chan
Publication of WO2010005279A1 publication Critical patent/WO2010005279A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
    • B31F—MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
    • B31F1/00—Mechanical deformation without removing material, e.g. in combination with laminating
    • B31F1/20—Corrugating; Corrugating combined with laminating to other layers
    • B31F1/24—Making webs in which the channel of each corrugation is transverse to the web feed
    • B31F1/26—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions
    • B31F1/28—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions combined with uniting the corrugated webs to flat webs ; Making double-faced corrugated cardboard
    • B31F1/2845—Details, e.g. provisions for drying, moistening, pressing
    • B31F1/285—Heating or drying equipment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
    • B31F—MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
    • B31F1/00—Mechanical deformation without removing material, e.g. in combination with laminating
    • B31F1/20—Corrugating; Corrugating combined with laminating to other layers
    • B31F1/24—Making webs in which the channel of each corrugation is transverse to the web feed
    • B31F1/26—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions
    • B31F1/28—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions combined with uniting the corrugated webs to flat webs ; Making double-faced corrugated cardboard
    • B31F1/2845—Details, e.g. provisions for drying, moistening, pressing
    • B31F1/2877—Pressing means for bringing facer sheet and corrugated webs into contact or keeping them in contact, e.g. rolls, belts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
    • B31F—MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
    • B31F1/00—Mechanical deformation without removing material, e.g. in combination with laminating
    • B31F1/20—Corrugating; Corrugating combined with laminating to other layers
    • B31F1/24—Making webs in which the channel of each corrugation is transverse to the web feed
    • B31F1/26—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions
    • B31F1/28—Making webs in which the channel of each corrugation is transverse to the web feed by interengaging toothed cylinders cylinder constructions combined with uniting the corrugated webs to flat webs ; Making double-faced corrugated cardboard
    • B31F1/2845—Details, e.g. provisions for drying, moistening, pressing
    • B31F1/2877—Pressing means for bringing facer sheet and corrugated webs into contact or keeping them in contact, e.g. rolls, belts
    • B31F1/2881—Pressing means for bringing facer sheet and corrugated webs into contact or keeping them in contact, e.g. rolls, belts for bringing a second facer sheet into contact with an already single faced corrugated web

Definitions

  • This invention relates to a belt lifting device used during the production of corrugated board.
  • the segment of a corrugator line (machine producing corrugated board from paper rolls) between the double glue machine and the slitter scorer is known as the double baker.
  • the function of the double baker is to press the single facer (comprised of one flat paper call liner and one corrugated paper call fluting paper) into contact with one or two other single facer and with the outer liner (the flat paper that will be on the outside of the box), to pull the board throughout the machine, and finally to dry the glue as well as the board.
  • the first corrugator lines were produced before the 2 nd world war.
  • the double baker of the times used steel rollers to press a cotton belt into contact with the board.
  • steel chests heated with steam produced the heat necessary to dry the glue and the layers of paper.
  • SHS Simon Handling System
  • SHORT PRESS The SHS product was known as SHORT PRESS.
  • the weight rollers are replaced with a pressure system comprising an airbag inserted into an aluminium box.
  • the bottom part of the box is closed by flat stainless steel chains.
  • the airbag When the airbag is inflated, it presses down on the flat chains.
  • the chains press on the belt and the belt on the board.
  • This system gives a larger surface of pressure with less specific (per square cm) pressure.
  • the advantages of this system are: better heat transfer less board crush (higher board calliper and stronger boxes) better production control (every unit can be controlled independently and pressure can be adjusted.
  • the Interfic product is called THERMOBAR.
  • the Interfic product is called THERMOBAR.
  • the weight rollers are replaced with a pressure system composed of ski-like stainless steel plates (shoes). Those plates are attached to a bar that can be moved up and down by the mean of 2 air cylinders. Between the bar and the shoes is a spring. When the bar moves down, it compresses the springs and therefore presses the shoes press on the belt and the belt on the board.
  • This system gives a larger surface of pressure with less specific (per square cm) pressure.
  • the advantages of this system are: better heat transfer less board crush (higher board calliper and stronger boxes) - better production control (every unit can be controlled independently)
  • the challenge is to evaporate as much water (steam) as possible to get a board as dry and as stable as possible at the end of the machine.
  • the board is covered by the belt from entrance to exit of the double baker. Even with a substantially permeable belt, the board cannot freely evaporate and as board grade and the speed increases, the finished product is wet and soft. Even when the heat and pressure is increased to a maximum, the water is still trapped and the board remains wet.
  • the present invention relates to a device for lifting of a belt during a corrugation board production process.
  • a first pair of rollers known as a moving roller, set a few millimeters above the board surface to position the board in close proximity to the pressure applying means. This pair of rollers can be lifted when the machine stops by means of two air cylinders so that the operator can clean the hot-plate surface below the belt.
  • a second pair of rollers also known as a fixed roller is set to keep the belt as far as possible from the board surface (upper level).
  • a scraper blade is constantly cleaning this pair of rollers from pollution deposited on the belt such as wet starch, dust, paper.
  • two other rollers direct the belt from an upper level to the board surface level.
  • the present invention also relates to a device for lifting of a belt during a corrugated board production process comprising: a heating section providing increased evaporation of liquid from said corrugated board; a traction section located after the said heating section; a conveyor belt with a section thereof in contact with said corrugated board; at least one pair of moving rollers at a location above and substantially close to said corrugated board; at least one pair of fixed rollers positioned to keep the board away from the conveyor belt and then to direct the conveyor belt to said corrugated board; a scraper adapted to remove material from the at least one fixed pair of rollers; wherein the conveyor belt is separated from the corrugated board between said heating section and said traction section.
  • the pressure system used in this invention are, flat stainless steel chains loaded with ballast bars (steel bars cut at the require shape).
  • Figure 1 shows an overall view of the device in an embodiment of this invention.
  • Figure 2 shows a roller in an embodiment of this invention.
  • Figure 3 shows a scraper in an embodiment of this invention.
  • a pair of moving rollers (200) set a few millimeters above the board surface to position the board in close proximity to the pressure applying means, and to lift a conveyor belt (300).
  • a pair of fixed rollers (220) is set to keep the belt (300) as far as possible from the board surface (upper level).
  • a scraper blade (400) is constantly cleaning the pair of fixed rollers (220) and belt (300).
  • the pair of fixed rollers (220) direct the belt from an upper level to the board surface level.
  • a second pair of rollers also known as a fixed roller (220) is set to keep the belt as far as possible from the board surface (upper level).
  • a scraper blade (400) is constantly cleaning the pair of fixed rollers (220) from pollution deposited on the belt such as wet starch, dust, and paper. Just before the entrance of a traction section, the pair of fixed rollers (220) direct the belt from an upper level to the board surface level.
  • a heating section providing increased evaporation of liquid from said corrugated board (100); a traction section located after the said heating section; a conveyor belt (300) with a section thereof in contact with said corrugated board (100); a moving pair of rollers (200) at a location above and substantially close to said corrugated board (100); a fixed pair of rollers (220) positioned to keep the board (100) away from the conveyor belt (300); a scraper (400) adapted to remove material from the fixed pair of rollers (220); a means of directing the conveyor belt (300) to said corrugated board (100) comprising a pair of rollers (220, 240) spaced apart and in contact with opposing sides of the conveyor belt (300) wherein the conveyor belt is separated from the corrugated board (100) between said heating section and said traction section.
  • FIG. 2 there is shown a pair of moving rollers (200) in an embodiment of this invention.
  • This pair of moving rollers (200) is set a few millimeters above the board surface to position the board in close proximity to the pressure applying means.
  • This pair of moving rollers (200) can be lifted when the machine stops by means of two air cylinders so that the operator can clean the hotplate surface below the belt.
  • FIG. 3 shows a scraper (400) in an embodiment of this invention.
  • This scraper (400) is adapted to clean the pair of fixed rollers (220) and belt (300) by removing material deposited on the belt such as wet starch, dust, and paper.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Drying Of Solid Materials (AREA)

Abstract

A device for drying a layer of paper/board during a corrugation board production process comprises a heating section providing increased evaporation of liquid from said corrugated board, a traction section located after the said heating section, a conveyor belt (300) with a section thereof in contact with said corrugated board, at least one pair of moving rollers (200) at a location above and substantially close to said corrugated board, at least one pair of fixed rollers (220) positioned to keep the board away from the conveyor belt (300), a scraper (400) adapted to remove material from the at least one fixed roller (220), and a means of directing the conveyor belt (300) to said corrugated board wherein the conveyor belt (300) is lifted between said heating section and said traction section by the action of the said one pair of moving rollers (200) and one pair of fixed rollers (220).

Description

CORRUGATED BOARD PRODUCTION BELT LIFTING DEVICE
FIELD OF INVENTION
This invention relates to a belt lifting device used during the production of corrugated board.
BACKGROUND OF THE INVENTION
In the production of corrugated board, the segment of a corrugator line (machine producing corrugated board from paper rolls) between the double glue machine and the slitter scorer is known as the double baker. The function of the double baker is to press the single facer (comprised of one flat paper call liner and one corrugated paper call fluting paper) into contact with one or two other single facer and with the outer liner (the flat paper that will be on the outside of the box), to pull the board throughout the machine, and finally to dry the glue as well as the board.
History of double-baker technology:
The first corrugator lines were produced before the 2nd world war. The double baker of the times used steel rollers to press a cotton belt into contact with the board. Under the board, steel chests heated with steam produced the heat necessary to dry the glue and the layers of paper. This original technology still exists and is used in many existing machines.
In the early 80', Langston (USA) produced a machine using an air hood to press down on the belt. This technology disappeared at the end of the decade because it was not improving the board dryness sufficiently.
In 1993, two new technologies arrived into the market, one from Simon Handling System (SHS) of England and one from Interfic of USA. The SHS product was known as SHORT PRESS. With this technology, the weight rollers are replaced with a pressure system comprising an airbag inserted into an aluminium box. The bottom part of the box is closed by flat stainless steel chains. When the airbag is inflated, it presses down on the flat chains. The chains press on the belt and the belt on the board. This system gives a larger surface of pressure with less specific (per square cm) pressure. The advantages of this system are: better heat transfer less board crush (higher board calliper and stronger boxes) better production control (every unit can be controlled independently and pressure can be adjusted.
The Interfic product is called THERMOBAR. With this technology, the weight rollers are replaced with a pressure system composed of ski-like stainless steel plates (shoes). Those plates are attached to a bar that can be moved up and down by the mean of 2 air cylinders. Between the bar and the shoes is a spring. When the bar moves down, it compresses the springs and therefore presses the shoes press on the belt and the belt on the board. This system gives a larger surface of pressure with less specific (per square cm) pressure. The advantages of this system are: better heat transfer less board crush (higher board calliper and stronger boxes) - better production control (every unit can be controlled independently)
During the drying phase of the corrugated board production process, the challenge is to evaporate as much water (steam) as possible to get a board as dry and as stable as possible at the end of the machine. On all existing systems, the board is covered by the belt from entrance to exit of the double baker. Even with a substantially permeable belt, the board cannot freely evaporate and as board grade and the speed increases, the finished product is wet and soft. Even when the heat and pressure is increased to a maximum, the water is still trapped and the board remains wet. SUMMARY OF THE INVENTION
The present invention relates to a device for lifting of a belt during a corrugation board production process. A first pair of rollers known as a moving roller, set a few millimeters above the board surface to position the board in close proximity to the pressure applying means. This pair of rollers can be lifted when the machine stops by means of two air cylinders so that the operator can clean the hot-plate surface below the belt. A second pair of rollers also known as a fixed roller is set to keep the belt as far as possible from the board surface (upper level). A scraper blade is constantly cleaning this pair of rollers from pollution deposited on the belt such as wet starch, dust, paper. Just before the entrance of a traction section, two other rollers direct the belt from an upper level to the board surface level.
The present invention also relates to a device for lifting of a belt during a corrugated board production process comprising: a heating section providing increased evaporation of liquid from said corrugated board; a traction section located after the said heating section; a conveyor belt with a section thereof in contact with said corrugated board; at least one pair of moving rollers at a location above and substantially close to said corrugated board; at least one pair of fixed rollers positioned to keep the board away from the conveyor belt and then to direct the conveyor belt to said corrugated board; a scraper adapted to remove material from the at least one fixed pair of rollers; wherein the conveyor belt is separated from the corrugated board between said heating section and said traction section.
The pressure system used in this invention are, flat stainless steel chains loaded with ballast bars (steel bars cut at the require shape).
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows an overall view of the device in an embodiment of this invention.
Figure 2 shows a roller in an embodiment of this invention. Figure 3 shows a scraper in an embodiment of this invention.
DETAILED DESCRIPTION OF THE INVENTION
It should be noted that the following detailed description is directed to an apparatus and method for an improved corrugated board production process and is not limited to any particular size, shape or configuration of any individual parts of the device or the device as a whole.
Referring to Figure 1, there is shown below a pick up head surface a pair of moving rollers (200), set a few millimeters above the board surface to position the board in close proximity to the pressure applying means, and to lift a conveyor belt (300). A pair of fixed rollers (220) is set to keep the belt (300) as far as possible from the board surface (upper level). A scraper blade (400) is constantly cleaning the pair of fixed rollers (220) and belt (300). Just before the entrance of a traction section, the pair of fixed rollers (220) direct the belt from an upper level to the board surface level.
A pair of moving rollers (200), set a few millimeters above the board surface to position the board in close proximity to the pressure applying means. This pair of moving rollers (200) can be lifted when the machine stops by means of two air cylinders so that the operator can clean the hot-plate surface below the belt. A second pair of rollers also known as a fixed roller (220) is set to keep the belt as far as possible from the board surface (upper level). A scraper blade (400) is constantly cleaning the pair of fixed rollers (220) from pollution deposited on the belt such as wet starch, dust, and paper. Just before the entrance of a traction section, the pair of fixed rollers (220) direct the belt from an upper level to the board surface level.
There is also provided a heating section providing increased evaporation of liquid from said corrugated board (100); a traction section located after the said heating section; a conveyor belt (300) with a section thereof in contact with said corrugated board (100); a moving pair of rollers (200) at a location above and substantially close to said corrugated board (100); a fixed pair of rollers (220) positioned to keep the board (100) away from the conveyor belt (300); a scraper (400) adapted to remove material from the fixed pair of rollers (220); a means of directing the conveyor belt (300) to said corrugated board (100) comprising a pair of rollers (220, 240) spaced apart and in contact with opposing sides of the conveyor belt (300) wherein the conveyor belt is separated from the corrugated board (100) between said heating section and said traction section.
Referring now to Figure 2, there is shown a pair of moving rollers (200) in an embodiment of this invention. This pair of moving rollers (200) is set a few millimeters above the board surface to position the board in close proximity to the pressure applying means. This pair of moving rollers (200) can be lifted when the machine stops by means of two air cylinders so that the operator can clean the hotplate surface below the belt.
Figure 3 shows a scraper (400) in an embodiment of this invention. This scraper (400) is adapted to clean the pair of fixed rollers (220) and belt (300) by removing material deposited on the belt such as wet starch, dust, and paper.
While several particularly preferred embodiments of the present invention have been described and illustrated, it should now be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are intended to embrace such changes, modifications, and areas of application that are within the spirit and scope of this invention.

Claims

1. A device (10) for drying material during a corrugated board (100) production process comprising: a heating section providing increased evaporation of liquid from said corrugated board (100); a traction section located after the said heating section; a conveyor belt (300) with a section thereof in contact with said corrugated board
(100); at least one pair of moving rollers (200) at a location above and substantially close to said corrugated board ( 100); at least one pair of fixed rollers (220) positioned to keep the board away from the conveyor belt (300); a scraper (400) adapted to remove material from the at least one fixed roller (220); and a means of directing the conveyor belt (300) to said corrugated board, wherein the conveyor belt (300) is lifted between said heating section and said traction section by the action of the said one pair of moving rollers (200 and one pair of fixed rollers (220).
2. A device (10) for drying material during a corrugated board (100) production process according to claim 1, wherein the means of directing the conveyor belt (300) to said corrugated board (100) comprises a pair of rollers (240, 260) spaced apart and in contact with opposing sides of the conveyor belt (300).
3. A device (10) for drying material during a corrugated board (100) production process according to claim 1 or 2, wherein the moving pair of rollers (200) can be removed to allow for maintenance of the surface below the said conveyor belt (300).
4. A device (10) for drying material during a corrugated board (100) production process according to any one of claims 1 to 3, wherein the scraper (400) is adapted to remove waste material from the conveyor belt (300).
5. A device (10) for drying material during a corrugated board (100) production process according to any one of the preceding claims, further comprising a pressure applying means for providing contact between the conveyor belt (300) and the corrugated board (100).
6. A device (10) for drying material during a corrugated board (100) production process according to any one of the preceding claims, wherein the scraper (400) further comprises a layer of material to reduce any or a combination of noise, friction and wear.
7. A device (10) for drying material during a corrugated board (100) production process according to claim 6, wherein the layer of material is felt.
8. A method for drying material during a corrugated board (100) production process comprising the steps of: heating the corrugated board (100); joining layers of the corrugated board (100) by applying pressure on opposing sides via a conveyor belt (300) system; and separating the conveyor belt (300) from the corrugated board (100) after the heating.
PCT/MY2008/000166 2008-07-07 2008-11-28 Corrugated board production belt lifting device WO2010005279A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
MYPI20082499 2008-07-07
MYPI20082499 2008-07-07

Publications (1)

Publication Number Publication Date
WO2010005279A1 true WO2010005279A1 (en) 2010-01-14

Family

ID=40349449

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/MY2008/000166 WO2010005279A1 (en) 2008-07-07 2008-11-28 Corrugated board production belt lifting device

Country Status (1)

Country Link
WO (1) WO2010005279A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3926483C1 (en) * 1989-08-10 1991-01-31 Bhs-Bayerische Berg-, Huetten- Und Salzwerke Ag, 8000 Muenchen, De
US6186209B1 (en) * 1996-10-29 2001-02-13 Albany International Corp. Impermeable corrugator belt for application on air bearing pressure zones of a corrugator machine
WO2006040575A1 (en) * 2004-10-16 2006-04-20 Simon Corrugating Machinery Ltd Heat transfer system
DE202006014724U1 (en) * 2006-08-07 2006-11-23 Wu, Kuan-Shiung, Yangmei Water removal structure for two-sided corrugated cardboard gluing machine has water removal region containing housing; gas flow in housing brings cardboard layers between housing, heating plates for close gluing, moves them forward together

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3926483C1 (en) * 1989-08-10 1991-01-31 Bhs-Bayerische Berg-, Huetten- Und Salzwerke Ag, 8000 Muenchen, De
US6186209B1 (en) * 1996-10-29 2001-02-13 Albany International Corp. Impermeable corrugator belt for application on air bearing pressure zones of a corrugator machine
WO2006040575A1 (en) * 2004-10-16 2006-04-20 Simon Corrugating Machinery Ltd Heat transfer system
DE202006014724U1 (en) * 2006-08-07 2006-11-23 Wu, Kuan-Shiung, Yangmei Water removal structure for two-sided corrugated cardboard gluing machine has water removal region containing housing; gas flow in housing brings cardboard layers between housing, heating plates for close gluing, moves them forward together

Similar Documents

Publication Publication Date Title
KR100808507B1 (en) Apparatus for producing spliced laver by peicing sheets of laver
US8562328B2 (en) Method and apparatus for producing figured veneer
US20020179229A1 (en) Corrugator double backer with combined driven and static holddown sections
JP2000034700A (en) Production of papermaking molded product and production system therefor
DK158236B (en) METHOD AND PLANT FOR TEMPERATURE TREATMENT OF A DRY-MANUFACTURED FIBER FLOOR, e.g. FOR KITCHEN ROLLER PAPER
US2166749A (en) Machine for undulatingly corrugating cardboard
CN206579304U (en) The belt wiper mechanism of ink-jet printing system used for textiles
WO2010005279A1 (en) Corrugated board production belt lifting device
KR101867841B1 (en) Paper sheet
US2972378A (en) Treatment by compression of fibrocement wet sheet material and the like
CN202595561U (en) High-speed paper machine
CN214727335U (en) Multi-station paper printing production device
US5666744A (en) Infrared paper drying machine and method for drying a paper web in an infrared paper drying machine
CN110588080A (en) Novel paperboard production device
MX2007015491A (en) Web handling apparatus and process for providing steam to a web material.
CN100489427C (en) Equipment of drying face paper of preprinting packing box
JP5868069B2 (en) Paper machine
US7494569B2 (en) Apparatus for cleaning a papermachine fabric
CN214027465U (en) Circle-pressing circle-forming explosion-proof wire device
CN215766325U (en) Drying mechanism for corrugated board
CN218020760U (en) Oil polishing device
CN217922653U (en) Digital printing machine's swager constructs
CN202380353U (en) Paper making equipment
AU2002313120B2 (en) Refurbishing sheets of plastics
CN220925865U (en) Winding equipment

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 08876200

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 08876200

Country of ref document: EP

Kind code of ref document: A1