JPH0699065B2 - Reversing and discharging device for recording paper - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement of a reversing and discharging device for recording paper, which is attached to a recording machine such as a thermal printer or an electrostatic copying machine.

(Prior Art) When stacking the recording paper discharged in a conventional general recording machine on the discharge tray as it is, the arrangement order of the recording paper is opposite to the recording order. Therefore, page alignment must be performed after recording. However, it is complicated. In order to save this trouble, for example, as shown in Japanese Utility Model Application Laid-Open No. 58-41739, the recording paper guided through a paper discharge roller composed of a drive roller and a press roller provided in the paper discharge section of the recording machine is guided. A recording paper reversing device equipped with an outer guide and an inner guide, and a discharge roller for discharging the recording paper to the outside of the machine is detachably and rotatably attached to the above-mentioned paper discharge portion of the recording machine. It is known that the recording paper is turned over to automatically perform page alignment.

By the way, when the recording paper reversing device is mounted, the recording paper discharge path becomes longer, so if the recording paper reverse discharge operation is controlled at the same timing as the normal discharging operation, the recording paper discharge is completed. It is not possible to do so, and a paper jam will occur in the reversing device. Therefore, two types of control circuits are provided in the recording machine, one for mounting the reversing device to reversely eject the recording paper and one for removing the recording paper for normal ejection, and control the recording machine at different timings. However, there is a problem that the structure becomes complicated in this case. Further, it is conceivable that the control circuit may be of one type by being configured to control at the same timing as in the case of performing the above-mentioned reverse discharge when performing the normal discharge, but according to this configuration, the reverse device is provided. There is a problem that the discharge time becomes too long when the normal discharge is performed, and the ink sheet is unnecessarily wound and wastefully consumed.

(Object of the Invention) The present invention has been made in order to solve the above-mentioned problems, and in the case where reversal discharge of recording paper and normal discharge are controlled at the same timing by using one type of control circuit. Also, the recording paper can be completely ejected without causing paper jam in the reversing path of the recording paper during reverse ejection, and the waste of the ink sheet can be prevented from being wastefully consumed during normal ejection. A discharge device is provided.

(Structure of the Invention) The present invention is a reversing and ejecting device for a recording paper, which is detachably attached to a paper ejecting portion of a recording machine, and which reverses the recording paper led out through a paper ejection drive roller of the recording machine. It has an inversion path consisting of an outer guide and an inner guide for guiding while guiding, an inversion discharge roller provided at the tip of this inversion path, and a transmission mechanism for transmitting the rotational force of the paper discharge drive roller to the inversion discharge roller. Then
It is necessary to set the conveying force of the reverse discharging roller to a value larger than the conveying force of the paper discharge driving roller and to discharge the recording paper by the reverse discharging roller to the reverse discharging section via the discharge path and the reverse path. The length of the discharge path and the total length of the discharge path and the length of the discharge path are set so that the time and the time required to discharge the recording paper to the discharge section via the discharge path by the discharge drive roller are substantially equal. The peripheral speed of the reverse discharge roller and the peripheral speed of the paper discharge drive roller are set in correspondence with the ratio.

With this configuration, the discharge speed when reversing and ejecting the recording paper is set higher than that when normal ejection is performed by the addition of the reversal path, and the time required for ejecting the recording paper is set to be approximately equal. I am trying to do it.

(Embodiment) FIGS. 1 and 2 show a schematic configuration of a thermal printer as a recording machine provided with a recording paper reversal discharge device according to the present invention. The body of the thermal printer is composed of an upper frame 1 and a lower frame 2. The lower frame 2 has a support shaft 4 for the roll-shaped ink sheet 3.
And a winding device 5 for winding the ink sheet 3.
A thermal head 6 and a separation roller 7 are provided. Further, in the upper frame 1, idle rollers 8, 8 for guiding the ink sheet 3 to the thermal head 6, a platen roller 9 facing the thermal head 6, and a paper feed cassette 11 containing a recording paper 10 having a predetermined size. A tray unit 14 having a paper discharge tray 12 and a manual feed tray 13 and a paper discharge drive roller 15 are provided.

A feeding roll 16 is provided above the paper feeding cassette 11, and the recording paper 10 is fed into the paper feeding cassette 11 by a feeding roller 16.
A compression spring 17 is provided that biases the compression spring 17 toward. The recording paper 10 fed from the paper feed cassette 11 is supplied between the thermal head 6 and the platen roller 9 via a paper feed path 18 composed of upper and lower guide plates and a pair of upper and lower registration rollers 19. Then, by applying a heat pulse from the thermal head 6 in this portion, the ink of the ink sheet 3 is transferred to the recording paper and recording is performed. After that, the recording paper is separated from the ink sheet 3 via the separation roller 7 and is turned over to the paper discharge section of the upper upper frame 1 by the reverse discharge device 20.
When is installed, it is discharged to the outside of the machine through this.

As shown in FIG. 3, the reversing discharge device 20 has a discharge path A from a recording portion between the thermal head 6 and the platen roller 9 to a lead-out portion between the discharge driving roller 15 and the pressing roller 21. The reversing path B formed by the outer guide 22 and the inner guide 23 for reversing and guiding the recording paper led out through it, and the reversing discharge roller 24 provided so as to face the tip of the outer guide 22.
And a holding unit 25 that holds the discharged recording paper. The inverted U-shaped engaging groove 26 formed at the front end portion of the reversal discharge device 20 is engaged with the rotation support shaft 27 which is a fulcrum of rotation provided on the inner surface of the upper frame 1 so as to be reversed. The discharge device 20 is detachably attached to the discharge portion of the thermal printer and is rotatable about the rotation support shaft 27. Then, as shown in FIG. 4, the reversing discharge device 20 is rotated in the arrow direction R ₁ about the rotation support shaft 27 to open the discharge portion of the thermal printer and discharge the pressing roller 21. It is constructed so that it can be separated from the drive roller 15.

The outer guide 22 is formed by a plate material projecting at predetermined intervals on the inner surface of a cover plate 29 rotatably attached about a pivot 28 at the base end, and the curved shape formed on the plate material. The notch surface constitutes the guide surface of the recording paper. The outer guide 22 can be separated from the reversal discharge roller 24 and the inner guide 23 by rotating the cover plate 29 around the pivot 28 in the arrow direction R ₂ to open it.
In this state, the paper jam generated in the reverse path B can be easily removed. A compression spring 30 for urging the lower end of the cover plate 29 outward is disposed below the pivot 28. The urging force of the compression spring 30 causes the outer guide 22 to reverse when the outer guide 22 is in a normal state. It is designed to be positioned close to the inner guide 24 and the inner guide 23. Also,
The pressing roller 21 is a sheet discharge driving roller 15 via a leaf spring 31.
It is attached to the inner guide 23 in a state of being urged to the side, and in a normal state, the pressing roller 21 is brought into pressure contact engagement with the paper discharge drive roller 15.

Further, the reverse discharge roller 24 is configured to be rotationally driven by a transmission mechanism that transmits the rotational force of the paper discharge drive roller 15. That is, as shown in FIG. 5, a driven gear 33 that meshes with a drive gear 32 fixed to the side end portion of the paper discharge drive roller 15 is pivotally supported on the side end surface of the reversal discharge device 20 and is coaxial with the driven gear 33. First sprocket 34 provided above
Is connected via a chain to a second sprocket 35 provided at the side end of the reversing discharge roller 24, and the reversing discharge roller 24 is rotationally driven by a transmission mechanism 36 composed of this.

When the above-mentioned reversal discharge device 20 is removed and normal discharge is performed, as shown in FIG. 6, a detachable guide unit 39 having a guide plate 37 and a pressing roller 38 is attached to the discharge portion of the thermal printer by a solid line. Attach to the state. Then, the recording paper passes through the discharge path A from the recording portion between the thermal head 66 and the platen roller 9 to the lead-out portion between the discharge driving roller 15 and the pressing roller 38, and then onto the discharge tray 12. Is discharged.

When reversing and ejecting the recording paper, as shown in FIG. 3, the reversing and ejecting device 20 is installed in the paper ejection portion of the thermal printer instead of the guide unit 39. Then, the recording paper passes through the discharge path A from the recording section to the lead-out section and is then supplied to the reversing path B composed of the outer guide 22 and the inner guide 23, and the trailing end of the recording paper is connected to the thermal head 6 and the platen. When the recording sheet between the roller 9 and the roller 9 is passed, the recording sheet is discharged onto the holding section 25 at a speed corresponding to the peripheral speed of the reverse discharging roller 24. That is, the conveying force of the recording paper by the reversing discharge roller 24 is set to be larger than the conveying force of the paper discharge driving roller 15 and smaller than the conveying force of the platen roller 9, and the leading end of the recording paper is reversed. Discharge roller
After reaching 24, when the trailing edge of the recording paper passes between the thermal head 6 and the platen roller 9, the recording paper is ejected via the reversal ejection roller 24.

As described above, when the recording paper is reversed and discharged, the recording paper discharge path length is extended by a length corresponding to the reverse path B as compared with the case where the normal discharge is performed. Therefore, as will be described later, the total length of the discharge path A and the reverse path B of the recording paper,
To correspond to the ratio of the length of the discharge path A of the recording paper and the circumferential speed V ₁ of the above inversion discharge roller 24, by setting the circumferential speed V ₂ of the paper discharge driving roller 15, respectively, perform the reverse discharge The time required for the case and the time required for the normal discharge are configured to be substantially the same.

That is, the time required for the trailing edge of the recording sheet to pass through the discharge path A and the inversion path B when performing the above-mentioned reverse ejection is t ₁ , and the trailing edge portion of the recording paper during the normal ejection is Assuming that the time required to pass through the discharge path A is t ₂ , these discharge times t ₁ and t ₂ are expressed by the following equations.

t ₁ = (A + B) / V ₁ t ₂ = A / V ₂ The speed ratio of the peripheral speeds V ₁ and V ₂ required to set the discharge times t ₁ and t ₂ equal to each other is calculated by the formula shown below. Required based on Note that in order for the above expression of the discharge time t ₁ to hold,
The total length (A + B) of the recording paper discharge path A and the reverse path B is
It is necessary that the condition that the length in the conveyance direction of the recording paper (the total length of the recording paper) or less be satisfied.

_{(A + B) / V 1} = A / V 2 ∴V 1 = V 2 · (A + B) / A Thus, the peripheral speed V ₁ of the upper the reverse discharge roller 24 peripheral speed V ₂ of the paper discharge driving roller 15 By setting (A + B) / A times, it is possible to equalize the discharge time when the recording paper is reversed and discharged and when it is normally discharged. Therefore,
It is no longer necessary to employ a complicated configuration in which different control circuits separately control the case of performing reverse ejection of recording paper and the case of performing normal ejection as in the conventional apparatus. Various controls are possible. That is, since the discharge time is the same when performing the reverse discharge and when performing normal discharge, the discharge time at the time of reverse discharge is insufficient and paper jam occurs in the reverse discharge device 20, or the normal discharge is performed. Sometimes it is possible to prevent the situation that the ink sheet is excessively wound up and wasted unnecessarily due to excessive discharge time, and a single control circuit performs both the above-mentioned reverse discharge and normal discharge. It can be controlled properly.

In addition, as a means for setting the peripheral speed V ₁ of the reverse discharge roller 24 to be high, the diameter of the reverse discharge roller 24 is set to the discharge drive roller.
The method of making it larger than the diameter of 15
By changing the number of teeth of the first and second sprockets 34, 35, etc., the rotation speed of the reverse discharge roller 24 can be adjusted.
There is a method of increasing the rotation speed compared to. Further, the reversing discharge device 20 according to the present invention is not limited to the above thermal printer, but can be used for a discharge unit of an electrostatic copying machine, a laser beam printer, a facsimile, or the like.

(Effects of the Invention) As described above, according to the present invention, according to the length of the reversal path added by mounting the recording paper reversal discharge device,
By making the peripheral speed of the reverse discharge roller provided at the tip of the reverse path faster than the peripheral speed of the paper discharge drive roller provided at the base of the reverse path, the reverse discharge of the recording paper can be performed. Since the required time and the time required to carry out normal ejection are substantially equal to each other, it is possible to properly perform ejection control of recording paper with a simple structure using a single control circuit. it can. That is, unlike the conventional case, it is not necessary to perform the complicated control of differentiating the discharge time when the reverse discharge of the recording paper is performed by providing two kinds of control circuits and the discharge time when the normal discharge is performed, and When performing reverse ejection of recording paper, it is possible to prevent paper jams due to the ejection operation ending while the recording paper remains inside the reverse ejection device, and an ink sheet is needed more than necessary when performing normal ejection. There is an advantage that it can be prevented from being wasted and consumed wastefully.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a thermal printer equipped with a recording paper reversal discharge device according to the present invention, FIG. 2 is a sectional view of the thermal printer, and FIG. FIG. 4 is a cross-sectional view showing an essential part of the invention, FIG. 4 is a cross-sectional view showing an opened state of a reversing path of recording paper, FIG. 5 is a side view showing a driving part of a reversing discharge roller, and FIG. It is a sectional view showing the state where it was opened. 15 ... Paper ejection drive roller, 20 ... Reverse ejection device, 22 ... Outer guide, 23 ... Inner guide, 24 ... Reverse ejection roller, 36 ...
… Transmission mechanism, 12 …… Paper ejection tray (ejection part), 25 …… Holding part (reversal ejection part), A …… ejection path, B …… reversal path.

Claims (1)

[Claims] 1. A reversing and ejecting device for a recording paper, which is detachably mounted on a paper ejecting portion of a recording machine, and which guides the recording paper led out through a paper ejection drive roller of the recording machine while reversing the recording paper. The reversal path includes a reversal path including a guide and an inner guide, a reversal discharge roller provided at the tip of the reversal path, and a transmission mechanism that transmits the rotational force of the paper discharge drive roller to the reversal discharge roller. The conveying force of the discharge roller is set to a value larger than the conveying force of the paper discharge drive roller, and the time required for the reversing discharge roller to guide the recording paper to the reversing discharge unit via the discharge path and the reversing path is set. , The length of the discharge path and the total length of the discharge path and the reversal path are set to be substantially equal to the time required to guide the recording paper to the discharge section through the discharge path by the discharge drive roller. Correspondingly, the reverse discharge roller And the peripheral speed, the reverse discharge device for a recording sheet, characterized in that the peripheral speed of the discharging driving roller set respectively.