JPH0753120A - Paper conveying device - Google Patents

Abstract

PURPOSE:To surely detect a jam and to expand a detecting area by setting an optical path, which is formed by a light emitting part and a light receiving part, of a jam detecting sensor, so that it makes an acute angle with the direction perpendicular to the recording paper conveying direction. CONSTITUTION:As an optical path L makes an acute angle alpha with the lateral directional reference line H (a loop 6a is formed along this reference line H) in an optical sensor 31, the loop 6a of recording paper 6 is conveyed in the arrow 33 direction while interrupting the optical path L diagonally. Therefore, a duration when the optical path L is interrupted by the loop 6a is long, so that detection of the loop 6a is surely carried out. On the other hand, as the optical path L is diagonal, a detection area D is formed along the conveying direction 33 of the recording paper 6 between an installation position for a light emitting part 31a and the installation position for a light receiving position 31b. In other words, the loop 6a formed in the detection area D can be detected, and the detection area D is expanded in comparison with conventional one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper carrying device equipped with a sensor and a mechanism for carrying recording paper smoothly.

[0002]

2. Description of the Related Art Conventionally, jam detection in a paper carrying device is carried out by an optical sensor consisting of a light emitting portion and a light receiving portion arranged right next to the paper carrying surface, or by a flag which is displaced by contact of a recording paper. Is common.

The optical sensor uses a light emitting portion and a light receiving portion on each of the left and right sides of the sheet conveying surface so that the optical paths formed by these are parallel to the sheet conveying surface and are perpendicular to the sheet conveying direction. It is arranged so as to cross the direction directly, and when a part of the recording paper intercepts this optical path, it is detected as a jam. On the other hand, in the case of the flag, the swingable flag is lightly biased toward the paper transport surface so that when there is no recording paper on the paper transport surface, part of the flag projects from the paper transport surface. Constitute. Then, when the recording paper is normally conveyed, the protruding portion of the flag is pushed down by the back surface of the recording paper, and the recording paper is retreated from the conveyance surface. Therefore, when the recording sheet is jammed, that is, lifted up from the sheet conveying surface, a part of the flag projects from the sheet conveying surface. By detecting this movement, the recording sheet jam is detected.

As the recording paper on which the jam is detected by the above-mentioned optical sensor or flag, for example, continuous paper such as label paper is used. The label paper is a strip-shaped release paper called a separator, in which a large number of labels are releasably arranged and attached. This label paper is generally wound in a roll shape and held by a holding member so that the position of the winding center is constant. In use, a bar code or the like is printed by, for example, an image recording means while being unwound one after another by a conveying device.

[0005]

However, according to the above-mentioned conventional technique, there are the following three problems. According to an optical sensor whose optical path runs directly across the paper transport surface,
It is difficult to reliably detect a jam, and according to the flag, an erroneous detection due to vibration or the like may occur, or a jam of the label sheet may not be detected.

The case of an optical sensor will be described with reference to FIGS. The light emitting portion 31a and the light receiving portion 31b are provided on both left and right sides of the sheet conveying surface of the recording sheet 6 having a conveying direction in the direction of arrow 33.
An optical path (L) is formed by disposing an optical sensor (jam detection sensor) 31 having The light emitting portion 31a and the light receiving portion 31b are arranged at positions where the optical path L is slightly above the sheet conveying surface, parallel to the sheet conveying surface, and perpendicular to the conveying direction 33. That is, the optical path L crosses a little above the sheet conveying surface, just laterally. Therefore, as long as the recording sheet 6 is conveyed in a flat shape following the sheet conveying surface, the recording sheet 6 does not cross the optical path L described above. By the way, when the recording sheet 6 is jammed, the recording sheet 6 is continuously conveyed by the conveying means until the operation is stopped.
A loop 6a as shown in is formed. Further, when the recording paper 6 is a label paper, the peeling portion 35a may occur in the label 35 on the separator 6. These loops 6
The peeling section 35a and the peeling section 35a are formed to have the same vertical cross-sectional shape in the width direction at any position in the width direction. Therefore, the time during which the loop 6a and the peeling section 35a block the optical path L is recorded. The distance corresponding to the thickness of the paper 6 or the thickness of the label 35 is set to the recording paper 6 or the label 3.
The very short time it takes for 5 to pass. Therefore, erroneous detection is likely to occur, and the detection range in the carrying direction is very narrow. It should be noted that it is possible to increase the sensitivity of the optical sensor 31 in order to enable detection in a short time, but this increases the number of erroneous detections, making it impractical.

Next, the one using the flag will be described with reference to FIGS. 8, 9 and 10.

The flag 36 is provided on the conveyance guide (platen) 7
Has a swing center 36a below and is lightly urged upward. In the natural state, as shown in FIG.
The upper end portion is projected above the transport guide 7. In this state, the flag 36 does not block the optical path of the light transmissive sensor 37. As shown in FIG. 9, when the label paper 6 is conveyed along the upper surface of the conveyance guide 7, the flag 36 is pushed down by the back surface of the separator 35b, and at this time, the optical path of the light transmissive sensor is blocked. The state where the optical path is blocked is a state where the label paper 6 is normally conveyed. However, as shown in FIG. 10, even when the label 35 on the surface of the separator 35b is peeled off, the flag 36 takes a normal position and cannot detect the peeling off of the label 35. Since the holding means for holding the recording paper such as the label paper in a rolled state is fixedly provided, the central position thereof is fixed, and the winding diameter that is too large cannot be held. On the other hand, when holding a roll having a small winding diameter, space efficiency becomes poor. Similarly, since the center position of the roll-shaped recording paper is fixed, when the winding diameter is reduced due to printing, the unwinding position moves toward the center, which lowers the accuracy of conveying the recording paper.

Therefore, the present invention solves the above-mentioned three problems by making an acute angle in the optical path of the jam detection sensor and moving the position of the winding center of the recording paper. It is intended to provide.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is a conveying means (9a, 9b, 1) for conveying a recording sheet (6) along a sheet conveying surface (7a).
0a, 10b), and a jam detecting sensor (31) for detecting that a part of the recording paper (6) has deviated from the paper conveying surface (7a). Reference numeral 31) includes a light emitting portion (3a) forming a light path (L) and a light receiving portion (31b) on a plane substantially parallel to the paper transport surface (7a), and these light emitting portion (31a) and light receiving portion (31a). The optical path (L) formed by the section (31b) has an acute angle (α) with reference to a direction (H) perpendicular to the transport direction (33) of the recording paper (6). And

Further, holding means (40) for holding the belt-shaped recording paper (6) in a rolled state, and conveying means (9a, 9b, 10a, 10) for conveying the recording paper (6).
and a holding means (4).
0) is characterized in that it has adjusting means (41, 42) for moving the position of the winding center (5) of the roll-shaped recording paper (6).

Further, a holding means (3) for holding the band-shaped recording paper (6) in a rolled state and a conveying means (9a, 9b, 10a, 10) for conveying the recording paper (6).
b), the holding means (3) maintains the unwinding position (A) substantially constant as the outer diameter of the roll-shaped recording paper (6) changes. Characterize.

[0013]

[Operation] Based on the above configuration, the jam detection sensor (31)
By setting the optical path (L) of (1) to the acute angle (α) as described above, the optical path (L) diagonally intersects the loop of the recording paper (6), for example. Therefore, it is possible to take sufficient time for detection to perform reliable detection, and
The detection area (D) in the transport direction (33) can be enlarged.

Further, by moving the winding center (5) of the recording paper (6), various recording papers (6) having different winding diameters can be held without reducing space efficiency.

Furthermore, since the unwinding position (A) of the recording paper (6) is substantially constant, the conveyance of the recording paper (6) can be stabilized.

The reference numerals in the parentheses are given in view of the above circumstances and do not limit the configuration of the present invention.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. <Embodiment 1> FIG. 1 shows an outline of a printing apparatus to which a paper conveying apparatus according to the present invention is applied.

The printing device 1 has a box-shaped device body 2,
A holding member (holding means) 3 is fixed from the apparatus main body 2 toward the upper right in the figure. The holding member 3 rotatably supports the holding shaft 5 at its tip. A recording paper 6 made of continuous paper is wound around the outer circumference of the holding shaft 5 to form a paper roll 6A as a whole.

Inside the apparatus main body 2, a platen 7 for guiding the conveyance of the recording sheet 6 from below is horizontally long. The platen 7 is arranged upstream and downstream of the platen 7 in the conveying direction 33 of the recording sheet 6. Are conveying rollers 9a,
9b and discharge rollers 10a and 10b are provided.
The lower transport roller 9a of the upstream transport rollers 9a and 9b is a drive roller, and a driven pulley 13 paired with a drive pulley 12 that rotates integrally with the motor 11 is fixed to the roller 9a. A drive belt 15 is stretched between 12 and 13. A pulley 10c, which is integral with the lower discharge roller 10a on the downstream side, is connected to the driven pulley 13 via a drive belt 16 that circulates in the substantially left-right direction. Therefore, the rotation of the motor 11 is controlled by the drive rollers 15 and 16 and the like, and
a, the discharge roller 10a is rotated in the direction of the arrow to be transmitted. In this way, the upper transport roller 9b and the discharge roller 10b are driven to rotate in the arrow direction with respect to the lower transport roller 9a and the discharge roller 10a which are positively driven. The above-mentioned recording paper 6 has the upstream-side conveyance roller 9
a, 9b and the discharge rollers 10a, 10b on the downstream side while being unwound from the paper roll 6A, the platen 7
Is conveyed in the direction of arrow 33 following the upper surface of the sheet, that is, the sheet conveying surface 7a. A sensor 17 that detects the position of the recording sheet 6 that has been conveyed is disposed above the sheet conveying surface 7a.

A printing unit 20 is set on the paper transport surface 7a. A guide bar 19 is arranged vertically in the vicinity of the printing section 20 to guide the printing main body 21 up and down. The print main body 21 has a print head 22 for performing print recording on the recording paper 6 at the lower end portion thereof, and a rack 23 oriented vertically is fixedly provided on the side portion thereof. A gear 25 is meshed with the rack 23, and the gear 25
A drive belt 30 is stretched over the driven pulley 26 that is integral with the drive pulley 29 that is integral with the output shaft of the motor 27. Therefore, by rotating the motor 27 in the normal or reverse direction, the print main body 21 moves up and down along the guide rod 19, and the print head 22 retreats from the paper transport surface 7a or approaches the paper transport surface 7a. It is configured to be arranged at a predetermined printing position. Below the platen 7, there is a power supply 28 for supplying power to each part of the apparatus main body 2, an ink tank 32 for supplying ink to the print head 22, and above the discharge roller 10b, power supply to each part is controlled. Controller 34
Are arranged respectively.

On the upstream side of the printing section 20, a paper transport surface 7a is provided.
A light sensor 31 including a light emitting portion 31a and a light receiving portion 31b is disposed slightly above. As shown in FIG. 2, the light emitted from the light emitting portion 31a forms an optical path L and is received by the light receiving portion 31b. The optical path L is formed on a plane parallel to the sheet transport surface 7a, which is slightly above the sheet transport surface 7a on the upper surface of the platen 7, and is perpendicular to the transport direction 33 of the recording sheet 6. Is formed as a reference, and an acute angle α is formed with the reference line H.

In the printing apparatus 1 having the above-described structure, when a print command is generated, the controller 34 controls the power supply to each load, the motor 11 is driven first, and the conveying roller 9a rotates in the arrow direction, Move the recording paper 6 to the arrow 33
Transport in the direction. When the recording paper 6 is, for example, a label paper, the sensor 17 detects the leading end position of the label 35 at the same time when the conveyance is started. At the same time when the label 17 is detected by the sensor 17, the motor 27 is driven to move the print head 22 to a predetermined print position via the gear 25, the rack 23, etc.
When the label paper of which the leading edge is detected is conveyed to the printing unit 20, ink is ejected from the print head 22 to perform print recording. The recording paper 6 on which the print is recorded is discharged onto the discharge roller 10a,
10b is conveyed and discharged to the outside of the apparatus main body 2,
A series of operations ends. When the printing operation is continuously performed, the ink in the print head 22 is gradually consumed, so that the ink is supplied from the ink tank 32 so as to be always a constant amount.

The light emitting portion 31a and the light receiving portion 3 of the optical sensor 31.
1b monitors the conveyance state of the recording paper 6 and detects the occurrence of a jam or the like.

When a jam occurs, the conveying roller 9a, as shown in FIG.
Since 9b continues to convey the recording paper 6, a loop 6a is formed on a part of the recording paper 6. The optical sensor 31 detects the loop 6a, determines that the recording sheet 6 is not conveyed normally, stops the apparatus, and notifies the abnormality by a display or a buzzer.

As shown in FIG. 2, the optical sensor 31 has a horizontal reference line H (the loop 6a has this reference line H).
Has an acute angle .alpha. With respect to (formed along), this optical path L tends to cross the loop 6a at an angle. That is, the loop 6a of the recording paper 6 is conveyed in the direction of the arrow 33 while obliquely blocking the optical path L. Therefore, the optical path L is blocked for a long time by the loop 6a, and the loop 6a is reliably detected. Further, since the optical path L is oblique, the arrangement position of the light emitting portion 31a and the light receiving portion 3 are
The recording sheet 6 is conveyed in the conveying direction 33 between the arrangement position of 1b.
A detection region D is formed along the line. That is, the loop 6a formed in the detection area D can be detected, and the detection area D is significantly expanded as compared with the conventional case.

FIG. 3 illustrates a case where the recording paper 6 is a label paper, that is, a case where the labels 35, 35 ... Are releasably adhered to the surface of the strip-shaped separator 35b. The peeling portion 35a, which tends to be formed at the front end portion or the rear end portion of the label 35, diagonally crosses the optical path L as in the case of the loop 6a described above. Therefore, it can be detected with certainty as well. In particular, when the adhesive is applied to the back surface of the label 35, the adhesive often adheres to the print head 22 or is wound around the discharge roller 10b or causes a fatal phenomenon when conveyed in a peeled state. However, by ensuring the detection of the peeling portion 35a as described above, such a defect can be effectively prevented.

As another embodiment of the optical sensor 31, as shown in FIG. 5, a mirror 31c may be interposed between the light emitting portion 31a and the light receiving portion 31b. A wide detection area D can be formed by the pair of the light emitting portion 31a and the light receiving portion 31b through the mirror 31c.

Regarding the above-mentioned acute angle α of the optical path L,
In principle, there is no particular limitation, and it can be arbitrarily set according to other conditions such as the arrangement position of the optical sensor 31 based on the structural limitation of the apparatus body 2, the properties of the recording paper 6 to be printed, and the like. Just set it.

Further, in the above-mentioned embodiment, the optical path L is configured to be parallel to the sheet conveying surface 7a, but even if the optical path L is slightly tilted due to the restrictions of the structure of the apparatus,
It is possible to obtain substantially the same effect as described above. <Embodiment 2> In this embodiment, as shown in FIG. 11, a holding shaft (a winding center) of a holding means 40 for holding the paper roll 6A.
The position of 5 can be changed. Incidentally, reference numeral 46 in the figure denotes an interface for connecting with an external device.

The holding means 40 has a holding support plate 41 fixed to the apparatus main body 2 and a movable plate 42 which can move in and out of the holding support plate 41. A base end side of the moving plate 42 is formed so as to be able to move in and out with respect to the holding support plate 41, and a roll holding rod 43 for rotatably supporting the holding shaft 5 is provided on the tip end side.
Are projected horizontally. A pin insertion hole 41a is formed in the upper part of the holding support plate 41, while a plurality of adjustment holes 42a, 42a ... Are formed in the upper part of the moving plate 42. When the winding diameter of the paper roll 6A is large, the movable plate 42 is pulled out in the direction of the arrow 47a, and the adjustment hole 42a on the base end side of the movable plate 42 and the pin insertion hole 41a of the holding support plate 41 are formed.
Align the and and insert the adjustment pin 45. Conversely,
When the winding diameter of the paper roll 6A is small, the moving plate 42
Is inserted in the direction of the arrow 47b, the adjustment hole 42a on the front end side of the moving plate 42 and the pin insertion hole 41a of the holding support plate 41 are aligned, and the adjustment pin 45 is inserted. By doing so, in the case where the winding diameter is small and the conventional position adjustment of the holding shaft 5 is impossible, the occupied area shown by 49A in FIG. 14 is required, while 49B in FIG. 13 is required. It has become possible to use the occupied area shown in. That is, by making the holding shaft 5 movable, the position of the holding shaft 5 is adjusted according to the size of the winding diameter, the paper roll 6A having a large winding diameter can be used, and the paper roll 6A having a small winding diameter is used. When
Avoid wasting space.

In the above-mentioned embodiment, the holding means 40 is only extendable and contractible, but if the holding means 40 can be rotated further in order to minimize the space practically, the space can be made more efficient. Of course. <Third Embodiment> In the third embodiment, even if the winding diameter of the paper roll 6A held by the holding means 3 is changed, the unwinding position A of the paper roll 6A is substantially constant, and the conveyance accuracy of the recording paper 6 is improved. It is what makes me.

15 and 16 show a state in which the paper roll 6A is set on a holding member (holding means) 3 which is swingable about a fulcrum 3a. The holding member 3 is a compression spring 51.
Since the sheet roll 6A is always pulled by the guide 50 side with an appropriate force, the sheet roll 6A is pressed at a contact point with the guide 7, that is, the unwinding position A with a predetermined pressure. As described above, the recording paper 6 has the conveyance rollers 9a, 9
Although the sheet is conveyed by b, the sheet roll 6A is pressed by the guide 50, so that an appropriate tension is exerted to prevent sagging or twisting, and further, the sheet is conveyed in a state where the meandering is prevented.

When printing is continued, the winding diameter of the paper roll 6A decreases.

FIG. 17 is a diagram showing a state where the winding diameter of the paper roll 6A is reduced. As shown in FIG.
Even when the winding diameter of the
Because of the structure in which the sheet spring 6A is pulled by the compression spring 51 with the a as a fulcrum, the sheet roll 6A is appropriately pressed by the guide 50, and the recording sheet 6 is conveyed while preventing slack and twist and preventing meandering. If the holding member 3 is of a fixed type as in the prior art, as shown by the chain double-dashed line in FIG. 17, the winding diameter of the paper roll 6B is reduced and the conveyance rollers 9a, 9a.
Since the unwinding position B of the recording paper 6 with respect to b changes, the load acting on the conveyance rollers 9a and 9b also changes, and stable conveyance cannot be performed. Holding member 3 centered on the fulcrum 3a
In this embodiment, the load on the transport rollers 9a and 9b is substantially constant, and stable transport can be performed.

In the above-described embodiment, the holding member 3 swings about the fulcrum 3a, but even if the holding member 3 moves in parallel to the guide 50, the paper roll 6A may be moved. If the holding member 3 is displaced with a decrease in the winding diameter of the sheet roll, a predetermined tension is applied to the sheet roll 6A, and the supply position to the transport rollers 9a and 9b is stable, the above-described effect can be obtained. is there.

[0036]

As described above, according to the present invention,
By setting the optical path of the jam detection sensor at an acute angle with respect to the lateral direction, for example, the loop of the recording paper due to the jam crosses the optical path diagonally, so that the jam can be reliably detected and the detection area can be expanded. be able to.

Further, by making the position of the winding center of the recording paper wound in a roll shape movable, it is possible to cope well with recording papers having different winding diameters, and to avoid wasted space.

Furthermore, by keeping the unwinding position of the rolled recording paper substantially constant, the recording paper can be conveyed with high accuracy.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the configuration of a printing apparatus equipped with a paper transport device according to a first embodiment.

FIG. 2 is an operation explanatory diagram of the jam detection sensor according to the first embodiment.

FIG. 3 is an operation explanatory diagram of the jam detection sensor according to the first embodiment when the recording sheet is a label sheet.

FIG. 4 is a perspective view showing a state of the recording paper when a jam occurs.

FIG. 5 is an operation explanatory diagram of another jam detection sensor according to the first embodiment.

FIG. 6 is an operation explanatory view of a conventional jam detection sensor.

FIG. 7 is an operation explanatory diagram of a conventional jam detection sensor when a recording sheet is a label sheet.

FIG. 8 is an operation explanatory diagram of a jam detection sensor using a conventional flag.

FIG. 9 is an operation explanatory diagram of a jam detection sensor using a conventional flag.

FIG. 10 is an operation explanatory view of a jam detection sensor using a conventional flag.

FIG. 11 is a vertical cross-sectional view showing the configuration of a printing apparatus in which the paper conveying apparatus according to the second embodiment is mounted.

FIG. 12 is an enlarged perspective view showing the structure of the holding means of the second embodiment.

FIG. 13 is a schematic diagram showing the operation of the holding means of the second embodiment.

FIG. 14 is a schematic diagram showing the operation of a conventional holding unit.

FIG. 15 is a vertical cross-sectional view showing the configuration of a printing apparatus equipped with the paper carrying device of the third embodiment.

FIG. 16 is an operation explanatory diagram of a holding unit according to the third embodiment.

FIG. 17 is a diagram showing a comparison of operations of the holding means of the third embodiment and the conventional holding means.

[Explanation of symbols]

 3 Holding Means (Holding Member) 5 Holding Shaft (Center of Winding) 7a Paper Conveying Surface 6 Recording Paper (Label Paper) 6A Paper Roll 9a, 9b Conveying Means (Conveying Rollers) 10a, 10b Conveying Means (Discharging Rollers) 31 Jam Detection Sensor (Optical sensor) 31a Light emitting part 31b Light receiving part 33 Conveying direction 40 Holding means (adjusting means) 41 Adjusting means (holding support plate) 42 Adjusting means (moving plate) A Unwinding position L Optical path α Acute angle

Claims (3)

[Claims] 1. A paper carrying device comprising a carrying means for carrying a recording paper along a paper carrying surface, wherein a jam detecting sensor detects that a part of the recording paper has deviated from the paper carrying surface. The jam detection sensor includes a light emitting section and a light receiving section that form an optical path on a plane substantially parallel to the sheet conveying surface, and the optical path formed by the light emitting section and the light receiving section is the same as that of the recording sheet. A paper conveyance device characterized by having an acute angle with respect to a direction perpendicular to the conveyance direction. 2. A paper transporting device comprising: a holding unit that holds a band-shaped recording sheet in a rolled state; and a transporting unit that transports the recording sheet, wherein the holding unit is the roll-shaped recording unit. A paper transporting device comprising: an adjusting unit that moves the position of the winding center of the paper. 3. A paper transporting device comprising: a holding unit that holds a band-shaped recording sheet in a rolled state; and a conveying unit that conveys the recording sheet, wherein the holding unit is the roll-shaped recording unit. A paper conveyance device characterized in that the unwinding position is kept substantially constant as the outer diameter of the paper changes.