EP0842883B1 - Rouleau d'alimentation de papier pour imprimante - Google Patents

Rouleau d'alimentation de papier pour imprimante Download PDF

Info

Publication number
EP0842883B1
EP0842883B1 EP19970308098 EP97308098A EP0842883B1 EP 0842883 B1 EP0842883 B1 EP 0842883B1 EP 19970308098 EP19970308098 EP 19970308098 EP 97308098 A EP97308098 A EP 97308098A EP 0842883 B1 EP0842883 B1 EP 0842883B1
Authority
EP
European Patent Office
Prior art keywords
paper feed
protuberances
feed roller
paper
roller
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.)
Expired - Lifetime
Application number
EP19970308098
Other languages
German (de)
English (en)
Other versions
EP0842883A1 (fr
Inventor
Hiroshi Sato
Takanobu Matsuura
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.)
Alps Alpine Co Ltd
Original Assignee
Alps Electric Co 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 claimed from JP28242796A external-priority patent/JPH10119374A/ja
Priority claimed from JP28242896A external-priority patent/JP3300235B2/ja
Priority claimed from JP05104497A external-priority patent/JP3352602B2/ja
Application filed by Alps Electric Co Ltd filed Critical Alps Electric Co Ltd
Publication of EP0842883A1 publication Critical patent/EP0842883A1/fr
Application granted granted Critical
Publication of EP0842883B1 publication Critical patent/EP0842883B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J13/00—Devices or arrangements of selective printing mechanisms, e.g. ink-jet printers or thermal printers, specially adapted for supporting or handling copy material in short lengths, e.g. sheets
    • B41J13/02—Rollers

Definitions

  • the present invention relates to a paper feed roller used for a paper feed mechanism of a printer and, more particularly, to a paper feed roller ideally used for a printer which is required to ensure highly accurate paper feed.
  • Serial printers such as ink-jet printers and thermal-transfer printers are extensively used as output devices for computers, word processors, etc.
  • the recording head is selectively driven to record one line of data on a recording sheet; upon completion of the recording of one line, the recording sheet is fed for one line for the next recording. This operation is repeated to accomplish predetermined recording.
  • Fig. 7 shows a thermal-transfer printer which is an example of such a serial printer; a tabular platen 2 is disposed approximately at the center of a frame 1 of the printer so that the recording surface thereof is almost vertical, and a carriage shaft 3 is disposed at a lower position in front of the platen 2 of the frame 1 such that it is parallel to the platen 2.
  • a flange-shaped guide 4 is formed at the front edge of the frame 1; and a carriage 5 is installed on the carriage shaft 3 and the guide 4 in such a manner that it can reciprocate along the carriage shaft 3 and the guide 4.
  • Installed at the front edge of the carriage 5 is a thermal head 6 which is opposed to the platen 2 and which is moved into contact with or away from the platen 2 by a driving mechanism not shown.
  • a ribbon cassette (not shown) which contains an ink ribbon and guides the ink ribbon between the platen 2 and the thermal head 6. Further disposed on the top surface of the carriage 5 are a take-up bobbin 7 for taking up the ink ribbon from the ribbon cassette and a feeding bobbin 8 for feeding the ink ribbon.
  • a paper inserting port 9 through which a recording sheet, not shown, is inserted; there is also a paper feed roller 10 for feeding the sheet inserted through the paper inserting port 9 toward the front of the platen 2, i.e. the recording section.
  • a pressure roller 11 pressed against the paper feed roller 10 is rotatably provided beneath the paper feed roller 10; a paper feed gear 12 is mounted on one side surface of the frame 1 such that it juts out and it is coaxial with the paper feed roller 10.
  • a motor gear 15 of a paper feed motor 14 Connected to the paper feed gear 12 is a motor gear 15 of a paper feed motor 14 via a plurality of transmission gears 13, 13; when the paper feed roller 10 is rotated by the paper feed motor 14 via the motor gear 15, the transmission gears 13, and the paper feed gear 12, the paper nipped between the paper feed roller 10 and the pressure roller 11 is fed.
  • the paper is inserted through the paper inserting port 9, clamped between the paper feed roller 10 and the pressure roller 11, and the paper feed motor 14 is driven to rotate the paper feed roller 10 to feed the paper to the recording start position.
  • the carriage 5 With the thermal head 6 pressed against the platen 2 via the ink ribbon and the paper, the carriage 5 is moved along the platen to selectively energize and drive the recording elements of the thermal head 6 in accordance with image information so as to selectively melt and transfer the ink of the ink ribbon to the paper, thereby performing desired recording.
  • the paper is fed by a predetermined amount before implementing the next recording.
  • the conventional paper feed roller 10 in the serial printer generally has a rubber roller main body attached around the outer periphery of the metallic shaft.
  • the rubber roller main body is elastically deformed when the pressure roller 11 is pressed against it, posing a problem in that the radius of the rubber roller changes and the accurate paper feed amount cannot be obtained.
  • the elastic deformation of the rubber roller is not axially even, then the lateral feeding amount of the rubber roller will be accordingly uneven, presenting a problem of "skew.”
  • a paper feed roller 10 which is composed of a columnar metallic shaft 10a provided with irregular ceramic particulates 16 of about 20 to about 50 microns attached thereto as shown in Fig. 8.
  • the surface of the paper feed roller 10 does not elastically deform even when the pressure roller 11 comes in pressure contact; further, the surface projections of the ceramic particulates 16 bite in the paper to provide an appropriate gripping force, thus permitting stable, high accurate paper feed.
  • Patent Abstracts of Japan, Vol. 096, no. 008, 30 August 1996, discloses a paper feed roller comprising a metallic shaft in which a plurality of protuberances projected by a press machining operation are arranged.
  • a paper feed roller used for a printer comprising a plurality of protuberances arranged in zigzag form by a press machining operation in an axial and/or a circumferential direction at the outer circumferential surface of a metallic shaft having a circular sectional shape, characterised in that said plurality of protuberances are formed so that the density thereof is lower in an area where a pressure roller, which is pressed against said paper feed roller and which nips paper between itself and said paper feed roller, is in pressure contact, while the density thereof is higher in an area where said pressure roller is not in pressure contact.
  • Fig. 1 and Fig. 2 shows, by way of background, a paper feed roller in which Fig. 1 is a top plan view of the paper feed roller, and Fig. 2 is an enlarged view of protuberances. This paper feed roller is not in accordance with the present invention.
  • a paper feed roller 20 composed of a metallic shaft 21 having a circular cross section are a plurality of protuberances 22 arranged at predetermined intervals longitudinally in the circumferential direction and the axial direction of the metallic shaft by plastically machining the metallic shaft 21.
  • Portions 23 where the protuberances 22 are formed are located at positions opposed to pressure rollers 25 which are indicated by chain lines and which are provided on a printer; the axial width of each of the portions 23 is slightly larger than the width of each of the pressure rollers 25.
  • Each of the protuberances 22 is shaped nearly like a semi-dome composed of a vertical plane oriented to the direction of rotation of the paper feed roller 20 and a quarter-sphere surface continuing from the vertical plane as shown in the enlarged view of Fig. 2; the interval between the protuberances 22 is 0.2 to 0.6 mm in the circumferential direction and 0.6 to 1.8 mm in the axial direction.
  • a vertical plane 22c of each of the protuberances 22 shaped like a semi-dome faces in the direction of rotation of the paper feed roller 20, and the vertical planes 22c of the same row of the plurality of the protuberances 22 are oriented in the same direction. Further, the orientations of the vertical planes 22c of the protuberances 22 of the two adjacent rows are opposite to each other, and the protuberances 22 in a plurality of rows are arranged in a zigzag pattern.
  • a plurality of rotatable pressure rollers 25 which can be pressed against the paper feed roller 20 are disposed at predetermined intervals. As illustrated, the width of each of the areas 23 where the protuberances are provided is made greater than the width of each of the pressure roller 25 to constitute the paper feed mechanism adapted to feed paper by clamping the paper between the paper feed roller 20 and the pressure rollers 25.
  • Fig. 3 shows the shape of the essential section of a punch 26 used for the press working in the manufacture of the paper feed roller 20.
  • the punch 26 has stopper sections 26a at both ends thereof; at the time of press working, the stopper sections 26a are held against a positioning section of machining equipment, not shown, to ensure dimensional accuracy of the protuberances to be formed.
  • the punch 26 is held against a shaft 21, the surface of the shaft 21 is cut and raised, and a slipper-shaped section is formed, the slipper-shaped section being composed of a depression 22b and the protuberance 22 which is shaped like the foregoing semi-dome.
  • the shaft 21 may be either solid or hollow as long as it has a circular cross section.
  • Teeth 27 of the punch 26 are shaped such that the projecting surfaces thereof differ in height; therefore, cutting and raising the surface of the shaft 21 automatically produces the differences in cutting depth and accordingly produces differences in the height of the formed protuberances 22.
  • one cycle of press working forms one row of the protuberances; in actual machining operation, two punches 26 are provided such that the teeth 27 thereof are set in the opposite directions from each other with the shaft 21 located therebetween, and also the positions of the teeth 27 of the two punches 26 are shifted by a half pitch in the axial direction of the shaft 21.
  • two rows are formed at the same time so that the two rows of the protuberances 22 are shifted by a half pitch and the orientations thereof are opposite from each other in the circumferential direction.
  • the shaft 21 Upon completion of one cycle of press working, the shaft 21 is turned by a predetermined angle for the next cycle of press working.
  • the predetermined angle is the angle at which the protuberances 22 facing in the opposite direction are formed by the other punch 26.
  • the vertical planes 22c of the protuberances 22 formed on adjoining rows when one lap of press working has been finished are oriented opposite from each other and the protuberances of the respective rows are laid out in a zigzag form.
  • the shaft 21 After completing one lap of the press working, the shaft 21 is moved longitudinally by a predetermined distance, and the protuberances 22 in the area opposed to the next pressure roller 25 are formed in the same manner. By repeating this series of press working, the paper feed roller 20 provided with the desired protuberances 22 can be obtained.
  • the sheet 30 is fed only by the frictional force of the paper feed roller 20, and it is required to lift the pressure rollers 25 by the thickness of the sheet against the load of the pressure rollers 25.
  • the number of protuberances 22 increases, that is, as the density of the protuberances 22 increases, the coefficient of friction relative to the sheet 30 increases, leading to a greater feeding power. This is advantageous especially for thicker paper such as postcards when the pressure rollers 25 are lifted higher.
  • the protuberances have two different heights as illustrated in Fig. 5, and both the tall and short protuberances 22 provide the frictional force applied to the sheet 30 until the sheet 30 is nipped between the paper feed roller 20 and the pressure rollers 25; in this case, the advantage obtained by more protuberances 22 is displayed and the frictional force applied to the sheet 30 increases with a resultant increase in the feeding power.
  • only tall protuberances 22a grip the sheet so as to provide the required grip.
  • the areas 23, wherein the protuberances are provided are formed at intervals by plastic working by a press in the portions where the pressure rollers 25 are pressed against the paper feed roller 20, so that the protuberances can be formed with accurate heights at lower cost.
  • the protuberances 22 do not come off the paper feed roller 20 even after an extended use, stable paper feed accuracy can be maintained for a long time of period as compared with the case where the ceramic particulates 16 are attached to the surface of the paper feed roller 20.
  • An outer end 25a of the pressure roller 25 which is pressed against the protuberance area 23 positioned at an axial end of the paper feed roller 20 is disposed inward from an end 30a of the sheet 30; hence, the entire surface of the pressure roller 25 is pressed against the paper feed roller 20 via the sheet 30 to provide a constant coefficient of friction relative to the sheet 30, thus leading to higher paper feed accuracy.
  • the same advantage provided by the paper feed roller 20 of the two different heights can be obtained by forming the protuberances 22e in the areas, against which the pressure rollers 25 are pressed, so that the density thereof is lower or sparser than that of protuberances 22d in the areas, against which the pressure rollers 25 are not pressed.
  • a still greater advantage can be obtained by making the protuberances 22e in the areas, against which the pressure rollers 25 are pressed, taller and by making the protuberances 22d in the areas, against which the pressure rollers 25 are not pressed, shorter.
  • pitches P1 and P2 are set to smaller values out of the foregoing ranges, the load applied to one protuberance 22 is dispersed and grows smaller, making it impossible to secure sufficient grip.
  • axial pitch P2 is too large, then an insufficient number of protuberances 22 bite in the sheet with a resultant insufficient gripping force; if circumferential pitch P1 is too large, then the OHP sheet warps excessively between the protuberances 22, adversely affecting the paper feed accuracy.
  • the sheet 30 would come in contact also with the outer peripheral surface of the paper feed roller 20 in addition to the protuberances 22, and the load is dispersed with a resultant insufficient grip of the protuberances 22 on the sheet 30.
  • the protuberances 22 are taller than 90 microns, then the leading edge of the sheet 30 would be caught by the protuberances when the sheet 30 is inserted, preventing the sheet 30 from being fed to the point where the paper feed roller 20 is in contact with the pressure rollers 25; as a result, a paper feed failure may occur or the protuberances 22 may excessively bite in the sheet 30, scratching the sheet 30.
  • the paper feed roller in accordance with the present invention is able to provide highly accurate, stable paper feed power in both forward and reverse directions regardless of the direction of rotation of the paper feed roller, in addition to the advantage in that good grip by the protuberances on the paper is secured, and stable paper feed accuracy can be maintained for an extended use since the protuberances do not come off the paper feed roller.
  • the foregoing plurality of protuberances of the paper feed roller are formed so that each of them is shaped nearly like a semi-dome composed of a vertical plane oriented to the direction of the rotation of the roller and a quarter-sphere surface continuing from the vertical plane, and the orientations of the vertical planes are alternately shifted for each row of protuberances; hence, the paper feed roller is capable of performing stable paper feed in both forward and reverse directions without scratching the paper.
  • the foregoing plurality of protuberances are formed so that the density thereof is lower in an area where the pressure roller, which is pressed against the paper feed roller and which clamps the paper between itself and the paper feed roller, is in pressure contact, while the density thereof is higher in an area where the pressure roller is not in pressure contact, thus causing all the protuberances to help feed the paper until the paper is nipped between the paper feed roller and the pressure rollers, then to allow the protuberances in the lower-density area, which are formed in the position opposed to the pressure roller, to sufficiently grip the paper after the paper has been nipped between the paper feed roller and the pressure rollers; hence, the paper feed roller is capable of ensuring stable paper feed.
  • the taller protuberances among the plurality of protuberances of the paper feed roller are formed to be 60 to 90 microns high, while the shorter protuberances are formed to be 30 to 55 microns, so that the taller protuberances may evenly act in feeding the paper after the paper has been clamped between the paper feed roller and the pressure rollers; hence, stable paper feed can be accomplished without causing the paper to skew.
  • the plurality of protuberances of the paper feed roller are arranged at pitches of 0.2 to 0.6 mm in the circumferential direction and at pitches of 0.6 to 1.8 mm in the axial direction; hence, the paper feed roller provides an appropriate gripping force, permitting stable paper feed.
  • the plurality of protuberances of the paper feed roller are formed to a height of 30 to 90 microns, so that the protuberances provide appropriate grip on paper, thus permitting stable paper feed and also accurate setting of the paper at a start position.

Landscapes

  • Delivering By Means Of Belts And Rollers (AREA)
  • Handling Of Cut Paper (AREA)

Claims (5)

  1. Rouleau d'alimentation de papier (20) utilisé pour une imprimante, comprenant une pluralité de protubérances (22) en saillie par suite d'une opération d'usinage à la presse sur la surface circonférentielle extérieure d'un arbre métallique (21) présentant une section transversale de forme circulaire, caractérisé en ce que ladite pluralité de protubérances est agencée en forme de zigzag dans une direction axiale et/ou circonférentielle et est formée de telle façon que sa densité est plus faible dans une zone où un galet presseur (25), qui est pressé contre ledit rouleau d'alimentation de papier (20) et qui serre le papier (30) entre lui-même et ledit rouleau d'alimentation de papier (20), est en contact par pression, alors que sa densité est plus élevée dans une zone où ledit galet presseur (25) n'est pas en contact par pression.
  2. Rouleau d'alimentation de papier selon la revendication 1, dans lequel les hauteurs desdites protubérances (22c) dans la zone où ledit galet presseur (25) est en contact par pression sont formées pour être plus hautes que les hauteurs desdites protubérances (22d) dans la zone où ledit galet presseur (25) n'est pas en contact par pression.
  3. Rouleau d'alimentation de papier selon la revendication 1, dans lequel ladite pluralité de protubérances a une hauteur de 30 à 90 microns.
  4. Rouleau d'alimentation de papier selon la revendication 1, dans lequel ladite pluralité de protubérances est agencée avec un pas circonférentiel de 0,2 à 0,6 mm et avec un pas axial de 0,6 à 1,8 mm.
  5. Rouleau d'alimentation de papier selon l'une quelconque des revendications précédentes, dans lequel ladite pluralité de protubérances a deux hauteurs différentes, les protubérances les plus hautes ayant 60 à 90 microns de haut et les protubérances les plus basses ayant 30 à 55 microns.
EP19970308098 1996-10-24 1997-10-13 Rouleau d'alimentation de papier pour imprimante Expired - Lifetime EP0842883B1 (fr)

Applications Claiming Priority (9)

Application Number Priority Date Filing Date Title
JP28242796 1996-10-24
JP282427/96 1996-10-24
JP28242896 1996-10-24
JP28242796A JPH10119374A (ja) 1996-10-24 1996-10-24 紙送りローラおよびその製造方法
JP282428/96 1996-10-24
JP28242896A JP3300235B2 (ja) 1996-10-24 1996-10-24 プリンタの紙送り機構
JP5104497 1997-02-19
JP51044/97 1997-02-19
JP05104497A JP3352602B2 (ja) 1997-02-19 1997-02-19 紙送り機構

Publications (2)

Publication Number Publication Date
EP0842883A1 EP0842883A1 (fr) 1998-05-20
EP0842883B1 true EP0842883B1 (fr) 2002-03-06

Family

ID=27294179

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19970308098 Expired - Lifetime EP0842883B1 (fr) 1996-10-24 1997-10-13 Rouleau d'alimentation de papier pour imprimante

Country Status (2)

Country Link
EP (1) EP0842883B1 (fr)
DE (1) DE69710846T2 (fr)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6023248A (ja) * 1983-07-18 1985-02-05 Nippon Bell Parts Kk 紙送りロ−ラ
JPH05221059A (ja) * 1992-02-13 1993-08-31 Seiko Epson Corp プリンタ装置の紙送りローラ
JP3271039B2 (ja) * 1994-09-14 2002-04-02 株式会社 塚田螺子製作所 高摩擦ローラ及びその製造方法
JP3626286B2 (ja) * 1995-11-06 2005-03-02 株式会社 塚田螺子製作所 紙送りローラ及びその製造方法

Also Published As

Publication number Publication date
DE69710846D1 (de) 2002-04-11
DE69710846T2 (de) 2002-06-27
EP0842883A1 (fr) 1998-05-20

Similar Documents

Publication Publication Date Title
US7661674B2 (en) Feeding device and image recording apparatus equipped with the feeding device
JP2002254736A (ja) 記録装置及び記録方法
EP1489030B1 (fr) Rouleau d'alimentation en feuilles et sa mèthode de fabrication
EP0861798B1 (fr) Dispositif d'alimentation en feuilles pour une imprimante
EP0842883B1 (fr) Rouleau d'alimentation de papier pour imprimante
US5083879A (en) Image recording apparatus
US20070018386A1 (en) Paper feed mechanism
US5018888A (en) Paper tension adjusting device and method for a printer
JP3481923B2 (ja) 紙送りローラの製造方法
JP3300235B2 (ja) プリンタの紙送り機構
US20150273858A1 (en) Printing Device
JPH10235955A (ja) 紙送り機構
JP3526169B2 (ja) 記録装置
JPH10119374A (ja) 紙送りローラおよびその製造方法
JP3626286B2 (ja) 紙送りローラ及びその製造方法
JPH10231042A (ja) 紙送り機構
JPS5812156B2 (ja) サ−マルプリンタの紙送り装置
JPS63441Y2 (fr)
JPH026173A (ja) リボン送り装置
JP2682698B2 (ja) サーマルヘッドの圧接制御方法
JPS584681Y2 (ja) 印字装置
JP4205995B2 (ja) 熱転写プリンタのシート送りローラ
JP3464594B2 (ja) 記録方法および記録装置
JPS631563A (ja) 高品位カラ−プリンタ
JPS627495Y2 (fr)

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

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

AX Request for extension of the european patent

Free format text: AL;LT;LV;RO;SI

17P Request for examination filed

Effective date: 19980605

AKX Designation fees paid

Free format text: DE FR GB

RBV Designated contracting states (corrected)

Designated state(s): DE FR GB

17Q First examination report despatched

Effective date: 20000331

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 69710846

Country of ref document: DE

Date of ref document: 20020411

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20021209

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20081013

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20081223

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20081001

Year of fee payment: 12

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20100630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091102

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20100501

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091013