JP2773051B2 - Recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention is to keep a constant feed amount even if the roll diameter of a roll-shaped recording medium changes, so that a good recorded image can be obtained. It relates to a recording device.

<Conventional technology> Conventionally, in a recording apparatus using a roll-shaped recording medium, the recording medium is conveyed to a recording head position, cut by a predetermined length after recording, and discharged outside the apparatus. It is configured to be paper.

In this apparatus, a tension is applied to the recording medium in order to prevent the recording medium from loosening or floating at the recording position.

For example, when a torque brake smaller than the conveying force of the recording medium is applied to a holding shaft for holding the recording medium in the form of a roll, and the recording medium is conveyed by a feeding roller located downstream of the recording unit in the conveying direction. In addition, the recording medium is in a state where tension is added in a transport path from the feeding roller to the holding shaft, and the recording medium can be prevented from being slackened or wavy on the recording head.

<Problems to be Solved by the Invention> When the torque braking force is set to be constant regardless of the roll diameter of the recording medium, the recording medium is not consumed much, and when the roll diameter is large, the torque braking force is increased. Although the tension acting on the recording medium by the force is small, as the roll diameter decreases as the recording medium is consumed, the tension acting on the recording medium by the torque braking force changes greatly.

Further, even when the recording medium is replaced with a new recording medium having a large roll diameter, the tension acting on the recording medium is smaller than that immediately before the replacement of the recording medium (when the recording medium is consumed and the roll diameter is reduced). Become smaller.

When the tension acting on the recording medium changes in this way, the feed amount by the conveying means slightly changes. That is, when the roll diameter is large, the tension force is small, so that the feeding amount is relatively large. When the roll diameter is small, the tension is large, so that the feeding amount is relatively small.

Such a change in the feed amount appears as an image defect such as expansion and contraction of the recorded image and image unevenness. For example, in an apparatus that records an image while a recording medium moves and passes through an image recording unit, a change in the feed amount appears as expansion and contraction of the recorded image.

That is, when the roll diameter is large, the feed amount is large, so that the feed speed is increased. On the other hand, as the roll diameter is reduced, the feed amount is reduced, the feed speed is reduced, and the recorded image is shrunk.

In a recording apparatus such as a serial printer, which conveys a recording medium to a recording position and stops, after recording for a certain recording width, conveys the recording medium by the recording width, and repeats recording again. There is a problem as described below.

That is, the feed amount of the recording medium sent after one printing scan differs depending on the size of the roll diameter. For this reason, for example, if the predetermined feed amount is set when the roll diameter is large, when the roll diameter decreases according to the consumption of the recording medium, the feed amount changes so small that the predetermined feed amount is not reached, and image unevenness occurs. I do.

FIGS. 8 (a) to 8 (c) are explanatory diagrams for explaining an image defect caused by a change in the feed amount of the recording medium.

In the case shown in FIG. 3A, a good image A can be obtained because the feed amount of the recording medium in the direction of the arrow PD coincides with the recording width T.

However, if the feed amount T 'of the recording medium in the direction of the arrow PD is smaller than the recording width T as shown in FIG. 3B, an image A' having an overlapping image t 'at the recording width end is obtained.

If the feed amount T ″ of the recording medium in the direction of the arrow PD is larger than the recording width T as shown in FIG. 3C, the image A ″ has a gap t ″ at the recording width end.

In recent years, an image recording apparatus that outputs a pictorial color image with a high definition of 400 dot / inch or more has been developed. In such a recording apparatus, it is necessary to suppress the above-described image overlap and gap to several tens μm or less. .

The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object thereof is to always maintain a constant feed amount even when the roll diameter of a recording medium changes, thereby causing image overlap and gaps. An excellent condition is to provide a recording apparatus capable of obtaining a recorded image.

<Means for Solving the Problems> A configuration of the present invention for achieving the above object includes a transport unit that transports a roll-shaped recording medium to a recording unit, and a recording unit that holds the recording medium at a recording unit position. Loading means for applying a conveying load to the recording medium by applying a holding force to the recording medium, detection means for detecting a roll diameter of the recording medium, and the recording medium based on a detection signal from the detection means. And a load varying means for varying the carrying load of the load means by changing the holding force according to the roll diameter of the roll.

<Operation> According to the above configuration, according to the change in the roll diameter of the recording medium, the holding force for holding the recording medium, which is the transport load, at the position of the recording unit is changed. The feed amount can be kept constant.

For example, the transport load is increased when the roll diameter of the recording medium is large, so that the feed amount of the recording medium is not excessively large, and the transport load is reduced as the roll diameter decreases. The load means is controlled so that the medium feeding amount does not become too small.

Thereby, even if the roll diameter of the recording medium changes, the feed amount of the recording medium is kept constant, and a good recorded image without overlapping images and gaps can be obtained.

<Embodiment> Hereinafter, an embodiment of the recording apparatus of the present invention will be described with reference to the drawings.

(First embodiment)

1 to 6 show a first embodiment of the present invention. FIG. 1 is a block diagram for explaining an embodiment of the present invention.
2 is a schematic side sectional view of the entire recording apparatus to which the present invention is applied, FIG. 3 is a perspective view of a portion near a platen, and FIG. 4 is a portion for supporting a roll-shaped recording medium and detection for detecting a roll diameter. FIG. 5 is a perspective view of the means, FIG. 5 is a block diagram of a control circuit, and FIG. 6 is a flowchart showing control contents.

First, an overview of the entire recording apparatus will be described with reference to FIG. 2. A cassette 2 on which a cut sheet-shaped recording medium (for example, cut recording paper) CS is loaded on the bottom side of the apparatus main body 1.
And a rotating shaft 3 supporting a roll-shaped recording medium RP, and a manual feed port 4 on one side (left side in FIG. 4) of the apparatus main body 1.

The transport path 5 for the cut sheet-shaped recording medium CS is inserted from the cassette 2 side, the transport path 6 for the roll-shaped recording medium RP is inserted from the rotary shaft 3 side, and inserted from the manual feed slot 4 side. The transport path 7 for the recording medium is transport rollers 8
The conveying paths 5, 6, and 7 join at a position near the conveying roller 8.

Rollers 5a, 5b, and 5c are arranged in the transport path 5, respectively, and the recording medium CS separated one by one by the cooperation of the pickup roller 5d and a separation claw (not shown) is transported to the transport roller 8. It is supposed to be sent.

A set roller 6a which guides the recording medium RP from the roll portion of the recording medium RP in the transport path 6 to the inside of the transport path 6 while pulling out the recording medium RP, and a roller 6b which sends the introduced recording medium RP to the transport roller 8 And a rotary cutter 6c for cutting the recording medium RP into a predetermined size.

The recording media CS, RP sent to the transport roller 8 via the transport paths 5, 6, 7 are guided to the platen 9 by a lower transport roller 10a such as a registration roller on the upstream side of the transport path 10 near the platen 9. The recording media CS and RP are conveyed by an upper conveying roller 10b on the downstream side near the platen 9 in the conveying path 10, and in this process, recording is performed by a recording head 11 as recording means, and the recording medium is discharged from an outlet 12. It is discharged outside.

Here, the transport path 5, rollers 5a, 5b, 5c, transport path 6, set roller 6a, roller 6b, transport path 7, transport roller 8, transport path 10, lower transport roller 10a, and upper transport roller 10b are the recording medium CS. , And RP to the recording head unit 11.

The recording head 11 includes a head holder 11a and an inkjet head 11b fixed to the head holder 11a.
And is arranged to face the platen 9. The head holder 11a is mounted on a carriage 13c which is guided by rails 13a and 13b of the recording section transport system 13 and moves in a direction perpendicular to the plane of FIG. 2 (from the front side to the back side, or from the back side to the front side). .

During image recording, the recording media CS and RP are held on the platen 9 in a stopped state, and the ink is ejected onto the recording media CS and RP by the inkjet head 11b while moving the carriage 13c in accordance with the image signal. , An image having a predetermined recording width T is recorded. After the recording for one line is completed, the transport rollers 10b are driven to transport the recording media CS and RP by the recording width T and stop, and thereafter, the recording for the recording width T is performed again. By repeating this operation sequentially, the recording medium
Record images on CS and RP.

Next, the platen 9 will be described in detail with reference to FIG. 1 and FIG.

As shown in FIG. 3, pulleys 10a ₁ , 10a are provided at one axial end of a lower transport roller 10a provided on the upstream side of the platen 9 and an upper transport roller 10b provided on the downstream side, respectively.
b ₁ is provided. A belt 14b is wound around the pulleys 10a ₁ and 10b ₁ and the pulley 14a of the transport motor 14, so that the rotational driving force of the motor 14 is transmitted to the lower transport roller 10a and the upper transport roller 10b. Has become.

The platen 9 has a hollow interior and a housing shape, and is connected via a tube 15 and a pressure sensor 16 to a blower 17 for exhausting the air inside the platen 9. When the blower 17 is operated, the suction surface of the platen 9 (recording head section)
A suction force acts on a large number of suction holes 9a provided in the surface portion facing the surface 11 and the recording media CS and RP are held on the platen 9 without slack by the suction force. That is, the platen 9, the blower 17 and the like are load means for applying a transport load to the recording media CS and RP.

Here, the tube 15 is branched by a pipe joint 15a between the pressure sensor 16 and the blower 17, and an electromagnetic valve 18 is provided at the branch portion 15b.

As shown in FIG. 1, the electromagnetic valve 18 is controlled by a control circuit 19 serving as a load varying means. The electromagnetic valve 18 changes the amount of air sucked from the branch portion 15b, thereby changing the suction hole 9a. Can be changed.

This suction pressure is applied to the recording medium R by the upper transport roller 10b.
When the suction pressure (transport load) is increased, the recording medium RP
When the feeding amount of the recording medium RP is reduced and the suction pressure (transport load) is reduced, the feeding amount of the recording medium RP is increased.

That is, by driving the electromagnetic valve 18 to change the suction pressure, the feed amount of the recording medium RP can be changed.
In other words, by driving the electromagnetic valve 18 to change the suction pressure, the feed amount of the recording medium RP that changes depending on the roll diameter can be kept constant.

FIG. 4 shows the holding shaft 3 for holding the roll-shaped recording medium RP, and a gear is provided at one axial end of the holding shaft 3.
3a is fixed, and a brake gear 20a fixed to the shaft of the torque brake 20 meshes with the gear 3a.

Here, the torque brake 20 applies a constant torque to the shaft like a powder brake or a brake using oil resistance.

When the recording medium RP in the form of a roll is transported in the apparatus main body 1, when the holding shaft 3 and the gear 3a rotate, the brake gear 20a meshes with the gear 3a. Will be involved. Due to this brake load, tension acts on the recording medium RP that reaches the platen 9 via the conveyance path 6, and the recording medium RP is conveyed without slack by this tension.

In the vicinity of the holding shaft 3, as shown in FIG.
A roll diameter detecting device 21 as a detecting means for detecting the roll diameter of the roll-shaped recording medium RP is arranged.

The base 21a of the roll diameter detecting device 21 is fixed to the apparatus main body 1 so as to be located near the holding shaft 3.
A swing arm 21c is rotatably mounted on a support shaft 21b fixed to one end in the longitudinal direction of the base 21a (end near the holding shaft 3).

A roller 21e is provided at one end (the recording medium RP side) of the swing arm 21c via a shaft 21d.
A tension coil spring 21f is provided between the other end of the base 21a and the other end in the longitudinal direction of the base 21a (a side away from the holding shaft 3) so that the roller 21e is pressed against the outer peripheral surface of the recording medium RP. It is urged toward the recording medium RP. Therefore, the recording medium RP
When the roll diameter changes, the swing arm 21 follows
c will rotate in the direction of arrow A shown in FIG.

A fan gear 21g is mounted on the support shaft 21b coaxially with the swing arm 21c, and the sector gear 21g is fixed to one end of the swing arm 21c. Therefore, the swing arm 2
When 1c rotates, the sector gear 21g also rotates.

A potentiometer 21h is fixed to a position near the other end in the longitudinal direction of the base 21a. A shaft 21i is provided between the potentiometer 21h and the sector gear 21g.
A gear train including idle gears 21j and 21k supported by the shaft 21 and an idle gear 21m supported by the shaft 21 is provided. When the swing arm 21c rotates, the rotation is
1g, transmitted to the potentiometer 21h via the idle gears 21j, 21k, 21m, and the turning angle of the swing arm 21c is detected by the potentiometer 21h.

Here, as described above, the swing arm 21c rotates following the roll diameter of the recording medium RP, and an output corresponding to the roll diameter of the recording medium RP is output from a potentiometer 21h that detects the rotation angle. can get. That is, the roll diameter of the recording medium RP can be detected by the potentiometer 21h.

Next, the control circuit 19 will be described in detail with reference to FIGS.

As shown in FIG. 5, the control circuit 19 includes a CPU 19a for controlling the entire apparatus, a ROM 19b for storing control contents and various data shown in FIG. 6, and a control circuit 19 used as a workstation of the CPU 19a. It comprises a RAM 19c for temporarily storing data and the like, an interface 19d and the like.

The input port of the interface 19d is connected to the potentiometer 21h and the pressure sensor 16. The output port of the interface 19d is connected to an electromagnetic valve drive circuit 22, a blower drive circuit 23, a print head drive circuit 24, a print section transport system drive circuit 25, and a motor drive circuit 26.

Here, the control circuit 19 controls the electromagnetic valve 18 by inputting a detection signal from the potentiometer 21h. In this embodiment, the control circuit 19 controls the electromagnetic valve 18 as shown in FIGS. 7 (a) to 7 (c), for example. .

In FIGS. 7 (a) to 7 (c), the vertical axis represents the branch 15
b represents the amount of air taken in from b, and the horizontal axis represents the roll diameter of the recording medium RP.

In the case shown in FIG. 7A, the suction amount is changed once within the use range of one roll-shaped recording medium RP. That is, when the detection signal from the potentiometer 21h is input and it is determined that the roll diameter has become small enough to reduce the feed amount of the recording medium RP, the electromagnetic valve 18
Is operated to increase the suction amount of the air sucked from the branch portion 15b and reduce the suction pressure of the suction hole 9a.

In the case shown in FIG. 3B, the suction amount is changed a plurality of times in accordance with the change in the roll diameter. As the roll diameter becomes smaller, the air suction amount is increased stepwise (a plurality of times). Thus, the suction pressure of the suction hole 9a is reduced stepwise.

In the case shown in FIG. 3C, the amount of air suction is continuously changed in accordance with the change of the roll diameter. Therefore, the roll diameter becomes smaller, so that the amount of air suction is increased linearly. The suction pressure of the suction hole 9a is linearly reduced.

Next, the case where recording is performed on the roll-shaped recording medium RP will be described with reference to the flowchart of FIG.

In this case, the electromagnetic valve 18 is controlled as shown in FIG.

First, in step S10, it is determined whether or not the recording start key is on (ON).
Move to S11.

In this step S11, the blower drive circuit 23 is driven to operate the blower 17.

Next, the process proceeds to step S12, and the potentiometer 21h
It is determined whether or not the roll diameter of the recording medium RP is smaller than a predetermined value based on the detection signal input from. If NO, that is, if the roll diameter of the recording medium RP has not decreased to the predetermined value, the process proceeds to step S13. If YES, that is, if the roll diameter of the recording medium RP has decreased to a predetermined value, the process proceeds to step S18.

In step S13, the electromagnetic valve 18 is operated by the electromagnetic valve drive circuit 22 so as to reduce the amount of air suctioned from the branch portion 15b (to increase the suction pressure of the suction hole 9a). At this time, a detection signal from the pressure sensor 16 is input, and it is confirmed whether or not the suction pressure is increased as set by the electromagnetic valve 18, and the electromagnetic valve driving circuit 22 controls the electromagnetic valve 18 until the set suction pressure is reached. Works.

Next, in step S14, the transport motor 14 is operated by the motor drive circuit 26 to feed the recording medium RP by a predetermined amount.

Next, proceeding to step S15, the recording head drive circuit 2
4. The recording unit transport system drive circuit 25 operates the recording head unit 11 and the recording unit transport system 13 to record one line on the recording medium RP.

Next, the process proceeds to step S16 to check for the presence or absence of a recording signal. If there is a recording signal (YES), the process proceeds to step S12 and the same operation is repeated. If there is no recording signal (NO), the process proceeds to step S17.

In step S17, the blower 17 is stopped to end the recording.

If it is determined in step S12 that the roll diameter of the recording medium RP is smaller than the predetermined value (in the case of YES), the process proceeds to step S18.

In this step S18, the electromagnetic valve driving circuit 22 operates the electromagnetic valve 18 so that the amount of air suctioned from the branch portion 15b is increased (the suction pressure of the suction hole 9a is reduced). At this time, the detection signal from the pressure sensor 16 is input,
It is confirmed whether or not the suction pressure is reduced as set by the electromagnetic valve 18, and the electromagnetic valve 18 is operated by the electromagnetic valve drive circuit 22 until the set suction pressure is reached.

Next, in step S19, the transport motor 14 is operated by the motor drive circuit 26 to feed the recording medium RP by a predetermined amount.

Then, the process proceeds to step S20, where the recording head driving circuit 2
4. The recording unit transport system drive circuit 25 operates the recording head unit 11 and the recording unit transport system 13 to record one line on the recording medium RP.

Next, the process proceeds to step S21 to check for the presence or absence of a recording signal. If there is a recording signal (YES), the process proceeds to step S12 and the same operation is repeated. If there is no recording signal (NO), the process proceeds to step S17, where the blower 17 is stopped and the recording is terminated.

When the suction pressure is changed according to the roll diameter of the recording medium RP in this manner, the feed amount of the recording medium RP is kept constant, and an increase in the feed amount is prevented.

For this reason, the feed amount does not change due to the change in the roll diameter of the recording medium RP, that is, the print width T and the feed amount do not change and change, and a good recorded image without image overlap and gaps is obtained.

[Other embodiments]

Further, in the above-described embodiment, the case where the ink jet type is used for the recording head unit 11 has been described. However, the present invention is not limited to this, and a thermal head using an ink sheet or the like may be used. The recording head is not limited to the serial type, and may be a line type recording head.

<Effects of the Invention> As described above, according to the present invention, the holding force for holding the recording medium, which is the transport load, at the recording unit position is changed according to the change in the roll diameter of the recording medium. In addition, the feed amount of the recording medium can always be kept constant, and even if the roll diameter of the recording medium changes, images can be superimposed, and a good recorded image with no gap can be obtained.

[Brief description of the drawings]

1 to 6 show a first embodiment of the present invention,
FIG. 1 is a block diagram for explaining one embodiment of the present invention, and FIG.
FIG. 3 is a schematic side sectional view of the entire recording apparatus to which the present invention is applied, FIG. 3 is a perspective view of a portion near a platen, and FIG. 4 is a portion for supporting a roll-shaped recording medium and a detecting means for detecting a roll diameter. FIG. 5 is a block diagram of a control circuit, FIG. 6 is a flowchart showing control contents, and FIG.
8A to 8C are graphs for explaining the control contents of the electromagnetic valve, and FIGS. 8A to 8C are explanatory diagrams for explaining an image defect in a conventional recording apparatus. 1 is an apparatus main body, 2 cassettes, 3 is a rotating shaft, 4 is a manual feed port, 5, 6, and 7 are transport paths, 8 is a transport roller, 9 is a platen, 9a is a suction hole, 10 is a transport path, and 10a is a lower transport. Roller, 10b is an upper conveying roller, 11 is a recording head unit, 11a is a head holder, 11b is an inkjet head, 12 is an outlet, 13 is a recording unit conveying system, 13a and 13b are rails, 13c is a carriage, 14 is a motor, 14a is a pulley, 14b is a belt, 15 is a tube, 15a is a fitting, 15b is a branch, 16 is a pressure sensor, 17 is a blower, 18 is a solenoid valve, 19 is a control circuit, 20 is a torque brake, and 20a is a brake gear. , 21 is a roll diameter detecting device 21, 21a is a base 21a, 21b is a supporting shaft 21c is a swing arm, 21d is a shaft, 21e is a roller, 21f is a tension coil spring, 21g is a sector gear, 21h is a potentiometer, and 21i is a shaft. , 21j and 21k are idle gears, 21 is a shaft, 21m is an idle gear, and 22 is an electromagnetic Drive circuit, the blower drive circuit 23, the 24 recording head drive circuit, 25 is a recording unit conveying system drive circuit, 26 is a motor drive circuit, 27 an electromagnetic valve, 28 an electromagnetic brake driving circuit.

Claims (3)

(57) [Claims] 1. A conveying means for conveying a roll-shaped recording medium to a recording means, and a conveying load is applied to the recording medium by applying a holding force for holding the recording medium at a position of the recording means. Loading means, detecting means for detecting the roll diameter of the recording medium, and changing the holding force according to the roll diameter of the recording medium based on a detection signal from the detecting means, And a load varying means for varying a transport load. 2. The apparatus according to claim 1, wherein the load changing means controls the load means to increase the transport load when the roll diameter of the recording medium is large, and to reduce the transport load as the roll diameter decreases. The recording apparatus according to claim 1, wherein 3. A suction force for sucking the recording medium onto a suction surface which is a recording means position is used as a holding force for holding the recording medium at a recording means position, and the suction force is used as the holding force. 3. The recording apparatus according to claim 1, wherein the recording medium is changed according to a change in a roll diameter of the recording medium.