CA1309428C - Sheet feeder - Google Patents
Sheet feederInfo
- Publication number
- CA1309428C CA1309428C CA000562529A CA562529A CA1309428C CA 1309428 C CA1309428 C CA 1309428C CA 000562529 A CA000562529 A CA 000562529A CA 562529 A CA562529 A CA 562529A CA 1309428 C CA1309428 C CA 1309428C
- Authority
- CA
- Canada
- Prior art keywords
- sheet
- feeding
- paper
- feeding roller
- feeder
- 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 - Fee Related
Links
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
- B41J13/10—Sheet holders, retainers, movable guides, or stationary guides
- B41J13/103—Sheet holders, retainers, movable guides, or stationary guides for the sheet feeding section
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H3/00—Separating articles from piles
- B65H3/02—Separating articles from piles using friction forces between articles and separator
- B65H3/06—Rollers or like rotary separators
- B65H3/0623—Rollers or like rotary separators acting at least during a part of each separation cycle on the articles in a direction opposite to the final separating direction
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Handling Of Cut Paper (AREA)
- Sheets, Magazines, And Separation Thereof (AREA)
- Handling Of Sheets (AREA)
Abstract
ABSTRACT
A sheet feeder for printer; wherein a feeding roller rotates in reverse direction to feeding-out direction for a very short time, and thus a rear end of sheet in a sheet cartridge is made contact a sheet; stopper provided at the rear end of the sheet cartridge for separating sticking sheets.
A sheet feeder for printer; wherein a feeding roller rotates in reverse direction to feeding-out direction for a very short time, and thus a rear end of sheet in a sheet cartridge is made contact a sheet; stopper provided at the rear end of the sheet cartridge for separating sticking sheets.
Description
1309~28 This invention relates to a sheet feeder for printer, particularly to that wherein undesirable plural sheets feeding is prevented.
Reference is now made to the accompanying drawings in which:
FIG. 1 is the sectional view of the color printer having the sheet feeder of prior art.
FIGs. 2 to 4 are the sectional views of the color printer having sheet feeder of the prior art for showing operation thereof.
FIG. 5 is a sectional view of a color printer having a sheet feeder embodying the present invention.
FIG. 6 is a sectional view of the paper cartridge in FIG. 5.
FIG. 7 is a circuit diagram of a control circuit of the paper cartridge of FIG. 5.
FIGs. 8A and 8B are time charts for showing an operation of the control circuit of FIG. 7.
FIG. 9 is a flow chart for showing feeding operation of the control clrcul~.
FIG. 1 is a sectional view of sheet feeder of prior art. In FIG. 1, an ink sheet 8 is conveyed to a take-up reel 10 from a feeding reel 9. The feeding roller 6 is moved in a direction shown by an arrow A in FIG. 1 and is made touch to a top paper 7 of stacked papers in a paper cartridge 5.
Then, by rotation of the feeding roller 6, the paper 7 is taken out from the paper cartridge 5 and is transferred to a platen roller 2. Further, the paper 7 is transferred between the platen roller 2 and a thermal head 1 by pinch rollers 3, 13~9428 4, and printing is ma~e with yellow ribbon 8 tsee FIG. 2) by a thermal head. When the yellow print operation is completed the paper 7 is transferred to a first paper passage 12.
Next, the paper 7 is transferred to a second paper passage 13 by reversely rotating the platen roller 2 as shown in FIG. 3.
Then, the paper 7 is printed with magenta ribbon by forward rotation of the platen roller 2 as shown in FIG. 4. Cyan print operation is carried out in the same manner as the operation of yellow or magenta print.
The structure of the above-mentioned conventional device suffers the problem that two or more papers are often taken out from the paper cartridge 5, thereby resulting in defect of printing. Therefore, it is necessary to prevent the problem of plural sheet taking-out.
It is an object of the present invention to solve the above-mentioned problem.
According to one aspect of the invention there is provided a sheet feeder comprising: a sheet case, a sheet stopper provided at rear end of said sheet case, wherein a touching surface of said sheet stopper is of a material having friction against a topmost sheet and elasticity, a feeder roller which, in feeding operation, touches the topmost sheet of stacked sheets in said sheet case, a feeding roller motor for driving said feeding roller, and motor driving means for feeding forward rotation current to said feeding roller motor for issuing said topmost sheet from said sheet case and a reverse rotation current to said feeding roller motor for a short time prior to feeding of said forward rotation current, thereby making rear end of said topmost sheet touch and push said sheet stopper, thereby causing separation of said top sheet.
In the present invention, the feeding roller rotates in reverse direction to feeding-out directions for a very short time, and thus the rear end of sheet in the sheet cartridge is made contact the sheet stopper provided at the rear end of the sheet cartridge. Therefore, even when two or more sheets are sticking each other, the sheets are separated by such reverse direction rotation of the feed.ing roller.
While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and contact, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.
':;.~
.
FIG. 5 shows a sectional view of sheet feeder of an embodiment of the present invention. An ink sheet 8 is conveyed to a take-up reel 10 from a feeding reel 9. A
feeding roller 6 is moved in direction shown by an arrow A in FIG. 1 so as to touch a top paper 7 (or other kind of sheet) of stacked papers in a paper cartridge 5. Then, the feeding roller 6 is rotated in reverse direction for a small angle as shown in FIG. 5, so that the rear end of paper is made touch a sheet stopper 14 provided at the rear end of the cartridge 5. Because the end part of the paper 7 is pushed to the sheet stopper, the top sheet is bent as shown in FIG. 5.
Therefore, the sheets are separated, even in case of close sticking of two or more forward direction for taking out the separated top paper 7 from the paper cartridge 5. The paper 7, thus taken from the paper cartridge 5, is transferred to a platen -~' 1 3~2~
roller 2. Further, the paper 7 is trans~erred to a position which i8 between the platen roller 2 and a thermal head 1 by means of pinch rollers 3, 4, and is printed with yellow ribbon (see FIG.2). When the yellow print operation is completed, the paper 7 i8 transferred to a first paper passage 12.
Next, the paper 7 is transferred to a second paper passage 13 by reversely rotating the platen roller 2 as shown in FIG.3. Then, the paper 7 is printed with magenta ribbon with rotation of the platen roller 2 as shown in FIG.4. Cyan print operation is carried out in the same manner as yellow or magenta print operation.
FIG.6 shows a sectional view of the cartridge 5.
At the rear end of the cartridge 5, the paper stopper 14 is provided. On a face of the stopper to be touched by the paper, a member 14a having elasticity and large friction in a direction of its surface, such as any one member of known hook and loop fastener, is provided.
FIG.7 is a block diagram of controi circuit 15.
The control circuit 15 has a driver 22, a controller 20, an output port 3~, ROM 32, CPU 34, RAM 36 and an input port 30. The driver 22 is provided for driving a motor 24 for rotating the feeding roller 6. CPU 34 detects the status of printer by inputting status signals from the input port 30 and controls the controller 20 and the positioning circuit 3 for feeding roller 6 by outputting . ., control signals from the OlltpUt port 3~. CPIJ 34 controls the printer in accordaDce with a computer program stored in ROM 32.
FIG.9 shows a flow chart of this program. CPU
34 controls the po~itioning circuit 40 through the output port 3~ to issue a command signal to contact the feeding roller 6 to the top sheet ~step Sl). Then, in step S2, CPU 34 outputs control pulses to the input terminal CU of the controller 20. When the control pulses are inputted to the input terminal CU of the controller 20t the controller 20 outputs pulse signals as shown in FIG.8A
from output terminals ~ 2 , ~3 and ~4. The driver 22 outputs signals corre~ponding to the pulse ~ignal~ as shown in FIG.8A for driving the stepping motor 24.
Therefore, the stepping motor 24 rotates in reverse direction.
Next, in ~tep S3, CPU 34 outputs control pulses to the input terminal CD of the controller 20. When the control pulses are inputted to the input terminal CD of the controller 20, the controller 2n output~ pul~e ~ignals as shown in FIG.8B from output terminals ~ 2 ~3 and . Therefore, the stepping motor 24 rotates in forward direction.
Although in the embodiment of the invention the ~heet feeder i8 applied for color thermal printer , in other modified embodiment~ of the invention the ~heet l~Og428 feeder i9 applied for mono-color thermal printer or dot-matrix printer (mechanical impact printer).
Although the invention has been described in its preferred form with a certain degree of particularity, it iB understood that the present disclosure of the preferred form has been changed in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and th0 scope of the invention as hereinafter claimed.
, ,
Reference is now made to the accompanying drawings in which:
FIG. 1 is the sectional view of the color printer having the sheet feeder of prior art.
FIGs. 2 to 4 are the sectional views of the color printer having sheet feeder of the prior art for showing operation thereof.
FIG. 5 is a sectional view of a color printer having a sheet feeder embodying the present invention.
FIG. 6 is a sectional view of the paper cartridge in FIG. 5.
FIG. 7 is a circuit diagram of a control circuit of the paper cartridge of FIG. 5.
FIGs. 8A and 8B are time charts for showing an operation of the control circuit of FIG. 7.
FIG. 9 is a flow chart for showing feeding operation of the control clrcul~.
FIG. 1 is a sectional view of sheet feeder of prior art. In FIG. 1, an ink sheet 8 is conveyed to a take-up reel 10 from a feeding reel 9. The feeding roller 6 is moved in a direction shown by an arrow A in FIG. 1 and is made touch to a top paper 7 of stacked papers in a paper cartridge 5.
Then, by rotation of the feeding roller 6, the paper 7 is taken out from the paper cartridge 5 and is transferred to a platen roller 2. Further, the paper 7 is transferred between the platen roller 2 and a thermal head 1 by pinch rollers 3, 13~9428 4, and printing is ma~e with yellow ribbon 8 tsee FIG. 2) by a thermal head. When the yellow print operation is completed the paper 7 is transferred to a first paper passage 12.
Next, the paper 7 is transferred to a second paper passage 13 by reversely rotating the platen roller 2 as shown in FIG. 3.
Then, the paper 7 is printed with magenta ribbon by forward rotation of the platen roller 2 as shown in FIG. 4. Cyan print operation is carried out in the same manner as the operation of yellow or magenta print.
The structure of the above-mentioned conventional device suffers the problem that two or more papers are often taken out from the paper cartridge 5, thereby resulting in defect of printing. Therefore, it is necessary to prevent the problem of plural sheet taking-out.
It is an object of the present invention to solve the above-mentioned problem.
According to one aspect of the invention there is provided a sheet feeder comprising: a sheet case, a sheet stopper provided at rear end of said sheet case, wherein a touching surface of said sheet stopper is of a material having friction against a topmost sheet and elasticity, a feeder roller which, in feeding operation, touches the topmost sheet of stacked sheets in said sheet case, a feeding roller motor for driving said feeding roller, and motor driving means for feeding forward rotation current to said feeding roller motor for issuing said topmost sheet from said sheet case and a reverse rotation current to said feeding roller motor for a short time prior to feeding of said forward rotation current, thereby making rear end of said topmost sheet touch and push said sheet stopper, thereby causing separation of said top sheet.
In the present invention, the feeding roller rotates in reverse direction to feeding-out directions for a very short time, and thus the rear end of sheet in the sheet cartridge is made contact the sheet stopper provided at the rear end of the sheet cartridge. Therefore, even when two or more sheets are sticking each other, the sheets are separated by such reverse direction rotation of the feed.ing roller.
While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and contact, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.
':;.~
.
FIG. 5 shows a sectional view of sheet feeder of an embodiment of the present invention. An ink sheet 8 is conveyed to a take-up reel 10 from a feeding reel 9. A
feeding roller 6 is moved in direction shown by an arrow A in FIG. 1 so as to touch a top paper 7 (or other kind of sheet) of stacked papers in a paper cartridge 5. Then, the feeding roller 6 is rotated in reverse direction for a small angle as shown in FIG. 5, so that the rear end of paper is made touch a sheet stopper 14 provided at the rear end of the cartridge 5. Because the end part of the paper 7 is pushed to the sheet stopper, the top sheet is bent as shown in FIG. 5.
Therefore, the sheets are separated, even in case of close sticking of two or more forward direction for taking out the separated top paper 7 from the paper cartridge 5. The paper 7, thus taken from the paper cartridge 5, is transferred to a platen -~' 1 3~2~
roller 2. Further, the paper 7 is trans~erred to a position which i8 between the platen roller 2 and a thermal head 1 by means of pinch rollers 3, 4, and is printed with yellow ribbon (see FIG.2). When the yellow print operation is completed, the paper 7 i8 transferred to a first paper passage 12.
Next, the paper 7 is transferred to a second paper passage 13 by reversely rotating the platen roller 2 as shown in FIG.3. Then, the paper 7 is printed with magenta ribbon with rotation of the platen roller 2 as shown in FIG.4. Cyan print operation is carried out in the same manner as yellow or magenta print operation.
FIG.6 shows a sectional view of the cartridge 5.
At the rear end of the cartridge 5, the paper stopper 14 is provided. On a face of the stopper to be touched by the paper, a member 14a having elasticity and large friction in a direction of its surface, such as any one member of known hook and loop fastener, is provided.
FIG.7 is a block diagram of controi circuit 15.
The control circuit 15 has a driver 22, a controller 20, an output port 3~, ROM 32, CPU 34, RAM 36 and an input port 30. The driver 22 is provided for driving a motor 24 for rotating the feeding roller 6. CPU 34 detects the status of printer by inputting status signals from the input port 30 and controls the controller 20 and the positioning circuit 3 for feeding roller 6 by outputting . ., control signals from the OlltpUt port 3~. CPIJ 34 controls the printer in accordaDce with a computer program stored in ROM 32.
FIG.9 shows a flow chart of this program. CPU
34 controls the po~itioning circuit 40 through the output port 3~ to issue a command signal to contact the feeding roller 6 to the top sheet ~step Sl). Then, in step S2, CPU 34 outputs control pulses to the input terminal CU of the controller 20. When the control pulses are inputted to the input terminal CU of the controller 20t the controller 20 outputs pulse signals as shown in FIG.8A
from output terminals ~ 2 , ~3 and ~4. The driver 22 outputs signals corre~ponding to the pulse ~ignal~ as shown in FIG.8A for driving the stepping motor 24.
Therefore, the stepping motor 24 rotates in reverse direction.
Next, in ~tep S3, CPU 34 outputs control pulses to the input terminal CD of the controller 20. When the control pulses are inputted to the input terminal CD of the controller 20, the controller 2n output~ pul~e ~ignals as shown in FIG.8B from output terminals ~ 2 ~3 and . Therefore, the stepping motor 24 rotates in forward direction.
Although in the embodiment of the invention the ~heet feeder i8 applied for color thermal printer , in other modified embodiment~ of the invention the ~heet l~Og428 feeder i9 applied for mono-color thermal printer or dot-matrix printer (mechanical impact printer).
Although the invention has been described in its preferred form with a certain degree of particularity, it iB understood that the present disclosure of the preferred form has been changed in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and th0 scope of the invention as hereinafter claimed.
, ,
Claims (2)
1. A sheet feeder comprising: a sheet case, a sheet stopper provided at rear end of said sheet case, wherein a touching surface of said sheet stopper is of a material having friction against a topmost sheet and elasticity, a feeder roller which, in feeding operation, touches the topmost sheet of stacked sheets in said sheet case, a feeding roller motor for driving said feeding roller, and motor driving means for feeding forward rotation current to said feeding roller motor for issuing said topmost sheet from said sheet case and a reverse rotation current to said feeding roller motor for a short time prior to feeding of said forward rotation current, thereby making rear end of said topmost sheet touch and push said sheet stopper, thereby causing separation of said top sheet.
2. A sheet feeder according to claim 1, wherein said sheet stopper is a loop-shaped member of a hook and loop fastener.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62-46348 | 1987-03-27 | ||
| JP4634887U JPS63154546U (en) | 1987-03-27 | 1987-03-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1309428C true CA1309428C (en) | 1992-10-27 |
Family
ID=12744638
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000562529A Expired - Fee Related CA1309428C (en) | 1987-03-27 | 1988-03-25 | Sheet feeder |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0284046B1 (en) |
| JP (1) | JPS63154546U (en) |
| CA (1) | CA1309428C (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW555651B (en) * | 1998-04-14 | 2003-10-01 | Fuji Photo Film Co Ltd | Paper feeding cassette printer for use with paper feeding cassette and paper feeding method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1005090A (en) * | 1973-04-18 | 1977-02-08 | Xerox Corporation | Reverse buckle sheet feeding apparatus |
| SE425378B (en) * | 1980-04-25 | 1982-09-27 | Datasaab Ab | SET AND DEVICE FOR CREATING A STACK OF SHEET FORMS, EXAMPLE PAYMENTS, AND ANY SELECTED THESE FORMS |
-
1987
- 1987-03-27 JP JP4634887U patent/JPS63154546U/ja active Pending
-
1988
- 1988-03-23 EP EP19880104657 patent/EP0284046B1/en not_active Expired
- 1988-03-25 CA CA000562529A patent/CA1309428C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63154546U (en) | 1988-10-11 |
| EP0284046A1 (en) | 1988-09-28 |
| EP0284046B1 (en) | 1991-10-09 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |