JPS62249859A - Recording paper transferring method - Google Patents

Abstract

PURPOSE:To eliminate a slip between a platen roller and the recording paper and prevent the unsatisfactory recording by transferring the recording paper with a sag perpetually kept between a recording paper transfer roller and the platen roller. CONSTITUTION: The recording paper 2 from a recording paper roller 1 is fed to a platen roller 5 by a transfer roller 4 and is recorded by a recording head 3. The trasfer roller 4 and the platen roller 5 are driven by a common pulse motor 9, and a clutch 10 is provided between the motor 9 and a pulse motor 5. At the time of starting the operation, the transfer roller 4 is driven with the clucth disengaged, and the recording paper 2 is fed to the platen roller 5. In this case, the platen roller 5 is stopped, thus a sag is generated between both rollers 2A for the recording paper 2. Under this condition, the clutch 10 is engaged, the platen roller 5 is driven, and the recording paper 2 is transferred with a sag 2A kept between both rollers. Accordingly, the load of the platen roller 5 is the load of only the sag portion, thus no slip is generated and the correct transfer can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a recording paper transport method in a recording apparatus in which a platen roller presses the recording paper against a recording head and transports the recording paper while recording.

2. Description of the Related Art Conventionally, as shown in FIG. 3, this type of apparatus includes a transport roller 24 that supplies the recording paper 2 unwound from the recording paper roll 1 to the recording head 3, and a conveyor roller 24 that supplies the recording paper 2 unwound from the recording paper roll 1 to the recording head 3, and conveys the recording paper 2 while pressing it against the recording head 3. platen roller 5, cutter 6, sensor 7
, has a discharge row 28 etc. for discharging the recording paper, and in the standby state, the leading edge of the recording paper 2 is at the position of the transport roller 24, and when recording, the transport roller 24 moves the leading edge of the recording paper to the recording head. 3 and the platen row 25, and then the fourth
As shown in the figure, the platen roller 5 was pressing the recording paper 2 against the recording head 3 while conveying it at a speed corresponding to the recording speed. Note that while the platen row 25 is transporting the recording paper 2, the transport roller 4 is disconnected from the drive source. To return the leading edge of the recording paper 2 to the standby position shown in FIG. 3, the leading edge of the recording paper 2 is conveyed to the position where it is detected by the sensor 7 as shown in FIG. This is done by rotating it in the opposite direction.

Problems to be Solved by the Invention However, with this configuration, the platen roller must pull out the recording paper from the recording paper roll during recording;
The load on the platen roller is increased, and slippage is likely to occur between the recording paper and the platen roller.In particular, the roll weight of the recording paper roll changes as the recording paper is consumed, so slippage increases depending on the size of the recording paper roll. There was a problem in that the recording area became smaller and smaller, resulting in recording defects.

The present invention has been made in view of the above-mentioned problems, and provides a recording paper conveyance method that allows recording paper to be constantly conveyed smoothly by a platen roller without causing slips, regardless of the size of the recording paper roll. The purpose is to provide.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention drives a conveyance roller disposed upstream of the recording head even when the recording paper is being conveyed by the platen roller to move the recording paper toward the recording head. The recording paper is conveyed by the platen roller and the conveyance roller, and at this time, the recording paper is always left slack between the platen roller and the conveyance roller.

Operation According to the present invention, with the above-described configuration, since there is always slack in the recording paper between the conveyance roller and the platen roller, the platen roller is only loaded with the load required to simply feed the recording paper between the conveyance roller and the platen roller. Therefore, there is no slippage between the platen roller and the recording paper.
The feeding speed of the recording paper accurately corresponds to the speed of the platen roller, making it possible to perform good recording.

EXAMPLES The present invention will be described in detail below. FIG. 1 is a schematic side view showing an example of a recording apparatus used to carry out the recording paper conveyance method of the present invention. In the figure, 1 is a recording paper roll, 2 is a recording paper, 3 is a recording head, 4 is a conveyance roller, 5 is a platen roller, 6 is a cutter, 7 is a sensor, and 8 is a discharge roller. Both the conveyance roller 4 and the platen roller 25 are connected to a pulse motor 9, which is the same driving source, and a clutch 10 is provided between the pulse motor 9 and the platen roller 5, which can connect and disconnect the driving connection.

Next, a recording paper conveyance method using the recording apparatus having the above configuration will be explained. During standby, the leading edge of the recording paper is on standby at the position of the conveyance roller 4, as in the conventional case. When starting recording,
First, the conveyance row 24 is driven by the pulse motor 9 and conveys the leading edge of the recording paper 2 toward the recording head 3 . At this time, the platen roller 5 is kept in a stopped state. Next, the leading edge of the recording paper 2 touches the recording head 3 and the platen roller 5.
Even when the recording paper reaches between the two, the conveyance by the conveyance roller 24 is continued, and two slack portions of the recording paper are created between the conveyance roller 24 and the platen roller 5. After a period of time long enough for an appropriate slack portion 2A to occur, the clutch 10 is connected, the platen roller 5 starts rotating, and at the same time as the platen roller 5 starts conveying, the recording head 3 starts recording. Thereafter, the pulse motor 9 drives the platen row 25 at a speed corresponding to the recording speed of the recording head 3, and performs recording while conveying the recording paper. Even during this recording, the conveyance roller 4 is driven by the pulse motor 9.
Recording paper is pulled out from the recording paper roll 1 and conveyed toward the recording head 3. Therefore, a slack portion 2A of the recording paper is always maintained between the platen roller 5 and the conveyance roller 4, as shown in FIG. Therefore, the platen roller 6 only needs to transport the recording paper of the two slack portions, and no large load is applied to the platen roller 25, so no slip occurs between the platen roller 5 and the recording paper 2. , the platen row 25 can always convey the recording paper 2 at an accurate speed. After recording is completed, the cutter 6 cuts off the recorded portion, and the recorded portion is transferred to the discharge roller 8.
The leading edge of the remaining recording paper 2 is returned to the transport roller 24, and the remaining recording paper 2 returns to its original standby state.

In the above embodiment, the conveyance roller 4 and the platen roller 5 are configured to be driven by a common drive source, and the driving timing of the conveyance roller 4 and the platen roller 5 when advancing the recording paper is staggered. Although a slack portion was created by this, this can be changed in various ways. For example, at the time of the first paper threading, a slack portion 2A is formed as shown in FIG.
Even after recording is finished and the paper is cut off with a cutter, the paper is only returned to the position shown in Figure 1.
In other words, the state shown in FIG. 1 may be used as a standby window, and the slack portion may be maintained regardless of whether it is on standby or during recording.

Alternatively, separate motors may be connected to the conveyance roller and platen roller, and the speed at which the conveyance roller and platen roller are driven by each motor may be different to cause slack in the recording paper on both sides. The timing of stopping may be varied to cause slack in the recording paper.

Effects of the Invention As is clear from the above description, the present invention has a conveyance roller disposed upstream of the recording head and a platen roller that presses the recording paper against the recording head to prevent slack in the recording paper between them. By configuring the recording paper to be conveyed in this state, there is always slack in the recording paper between the conveyance roller and the platen roller while the recording paper is being conveyed by the platen roller. The load is only applied to feed the recording paper between the conveyance roller and the platen roller, and there is no slippage between the platen roller and the recording paper, and the recording paper feeding speed is adjusted to the speed of the platen roller. This has the effect of enabling accurate correspondence and good recording.

[Brief explanation of drawings]

1 and 2 are schematic side views showing an example of a recording device used in the recording paper conveyance method according to the present invention, with FIG. 1 showing the state at the start of recording, and FIG. 2 showing the state during recording. . 3 and 4 are side views schematically showing a conventional recording apparatus, with FIG. 3 showing a standby state and FIG. 4 showing a recording state. 1... Recording paper roll, 2... Recording paper,
3... Recording head, 4... Conveyance roller, 5... Platen roller, 6... Cutter, 7... Sensor, 8... ...Discharge roller, 9...Pulse motor, 10...
clutch 0

Claims (1)

[Claims] A conveyance roller that conveys the recording paper toward the recording head and a platen roller that conveys the recording paper while pressing it against the recording head convey the recording paper with slack created in the recording paper between them. A recording paper conveyance method characterized by: