JPS6241151A - Pin feed construction for recorder - Google Patents

Abstract

PURPOSE:To maintain stable paper feed by providing on the way of a paper feed force transmitting path a load limiting means for producing a slip when a predetermined load is reached. CONSTITUTION:A slip roller 13 contacts a pin roller 10 through a slip surface 14 having a certain frictional force to produce a slip when the rotary load of the pin roller 10 reaches a predetermined value larger than the normal tension of a blank 1 and smaller than a holding force of a feed hole of the blank and a pin. Normally between the frictional force F1 and the holding forces, F2, F3 is established the relationship F2>F3>F1, and while a slip is produced between the platen roller 3 and the blank 1, the blank is fed by the pin roller 10 under a predetermined tension T1. When the frictional force F1 increases abnormally and F1>F3, a slip occurs between the slip roller 13 and the pin roller 10. In this case, since F2>F3 is always set, any force larger than F2 does not act on the blank 1 no matter how much the frictional force F1 of the platen roller 3 may be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a pin feed structure for feeding paper with feed holes in a recording device such as a printer, facsimile, or typewriter.

[Prior art]

In order to achieve stable paper feed in the paper feed mechanism of a recording device, continuous paper (fan-hold paper) with feed holes on both sides of the paper is used, and the paper is fed by sequentially engaging pins with the feed holes of the paper. A pin feed structure may be adopted.

As such pin feed structures, there are a push type pin feed structure arranged in front of the printing position and a tension type pin feed structure arranged on the exit side of the printing position.

The printing position is formed between a platen roller and a print head, and a pail roller is provided in pressure contact with the platen so as to apply a desired tension to the paper.

In addition, as the pin feed structure, the pin (feed)
There are types that use rollers and types that use pin (feed) tractors, and such pin feed structures are usually provided at two locations on both sides of the paper.

In such a paper feeding mechanism, stable paper feeding can be achieved by applying a desired tension to the paper between the pin feed structure and the platen.

This tension is generated by creating a difference in the feed amount between the pin feed structure and the platen, and by causing the paper to slide on the platen (specifically, at the pressure contact portion of the pail roller).

However, in this type of conventional pin feed structure,
When the diameter of the platen increases in a high temperature or high humidity environment, the amount of feed of the platen increases and the frictional force (feeding force) between the platen and the pail roller increases, making it difficult for paper to slip on the platen. As a result, the tension of the paper becomes excessive, causing problems such as the pin in the pin feed structure becoming detached from the feed hole of the paper, the paper being torn, and paper jams occurring.

Further, when the resistance on the paper supply side increases abnormally, excessive tension is generated in the paper, resulting in the same problem as described above.

〔the purpose〕

It is an object of the present invention to solve the problems of the prior art, to prevent the paper from lifting or tearing even when the frictional force between the platen and the paper becomes excessive, and to prevent the occurrence of paper jams. Therefore, it is an object of the present invention to provide a pin feed structure for a recording device that can maintain stable paper feeding.

〔overview〕

In the present invention, a predetermined load is applied to a paper feeding force transmission path from a drive source such as a paper feeding motor to a pin, which is larger than the normal paper tension and smaller than the holding τ force between the paper feeding hole and the pin. The above object is achieved by providing a load limiting means that causes slippage when the load is applied.

〔Example〕

The present invention will be specifically described below with reference to the drawings.

FIGS. 1 and 2 show a longitudinal section of a main part of a recording device having a pin feed structure and a cross section of the pin feed structure according to an embodiment of the present invention.

In FIG. 1, paper (recording paper) 1 is fed between a platen roller 3 and a print head 4 by a push-in type pin feed structure 2, and recording is performed by the print head.

When one line of printing is completed, the pin feed structure 2 feeds the paper by a predetermined amount. In this case, the platen roller 3
is also driven at the same time, and in cooperation with the pail roller 5 pressed against it, a desired frictional driving force (paper feeding force) is applied to the paper l.

The print head 4 is mounted on a carriage 6, and the carriage is moved along a guide shaft 7 in the width direction of the paper by a drive source (not shown), during which recording is performed.

A paper guide 8 is provided around the platen roller 3 to guide the paper 1 to a printing position.

As shown in FIGS. 1 and 2, the pin feed structure 2 includes a pin feed shaft 9 that is rotationally driven by a drive source such as a paper feed motor, a pin roller 10 that is rotated by the pin feed shaft, and the pin roller. Pins 11 are arranged on the circumferential surface of the pin roller 10 at a predetermined pitch and engage with feed holes in the paper (continuous paper) 1, and a paper presser 12 guides the paper 1 to the circumferential surface of the pin roller 10.

The platen roller 3 is driven at a slightly higher circumferential speed than the pin roller IO, and this speed difference applies tension to the paper 1 corresponding to the frictional driving force on the circumferential surface of the platen roller.

However, a sliding roller 13 is provided between the pin roller 10 and the pin feed shaft 9 as a load limiting means.

This smooth roller 13 always rotates integrally with the pin feed shaft 9, but is connected to the pin roller 10 via a rotating friction surface (sliding surface) 14.

That is, the sliding roller 13 is applied with a certain frictional force so that it will slip when the rotational load of the pin roller 10 reaches a predetermined value that is larger than the normal tension of the paper 1 and smaller than the holding force between the paper feed hole and the pin. It is connected to the pin roller 10 via a sliding surface 14 that exhibits the following properties.

Here, the frictional force between the platen roller 3 and the paper 1 is Fl,
If the holding force between the pin 11 and the feed hole of the paper 1 is F2, and the holding force between the slip roller 13 and the pin roller 10 is F3, then
Under normal conditions, the relationship F2>F3>Fl-・-・-・・-・+ll is established, and the paper is fed by the pin roller 10 with a predetermined tension T1 while the platen roller 3 and paper 1 slip. .

When the diameter of the platen roller 3 increases due to high temperature or high humidity, the frictional force F1 increases abnormally, and Fl>F3-.
−・・−−−−−−・When (2) occurs, a slip occurs between the sliding roller 13 and the pin roller 10.

In this case, since F2>F3 is always set, no matter how much the frictional force F1 of the platen roller 3 increases, the paper 1
A force greater than F2 does not act on .

Therefore, even if the frictional force of the platen roller 3 increases,
It is possible to prevent the paper 1 from floating or tearing in the pin feed structure 2, and it is possible to prevent paper jams from occurring.

Furthermore, even if the resistance on the supply side of the paper 1 increases abnormally and an excessive tension T2 is generated, if T2>F3, the pin roller 10 will slip and the setting is always F2>F3, so the above-mentioned As in the case, lifting and tearing of the paper 1 in the pin feed structure 2 can be prevented, and the occurrence of paper jams can also be avoided.

FIG. 3 shows an embodiment in which the present invention is applied to a tension type pin feed structure in which the pin feed structure 2 is provided on the exit side of the printing position.

This embodiment differs from the embodiment shown in FIG. 1 only in that a pin feed structure 2 is provided on the outlet side, and all other parts including the pin feed structure itself are substantially the same as in the case of FIG.
．． ; has a configuration.

Therefore, corresponding parts will be designated by the same reference numerals, and detailed description thereof will be omitted.

In addition, in this tension type pin feed structure, the pin roller I
By making the circumferential speed of O slightly larger than the circumferential speed of platen roller 3, desired tension T1 is applied.

In this embodiment as well, the frictional force between the platen roller 3 and the paper l is Fl, and the holding force between the pin 11 and the feed hole of the paper 1 is F.
2. The holding force between the sliding roller 13 and the pin roller 10 is F
3, under normal conditions F2>F3>Fl, and the paper is fed by the pin roller 10 under a predetermined tension T1.

Frictional force F1 of platen roller 3 increases abnormally (Fl>F
3) Even if the pin roller 10 slips and rotates, and F2
> Since it is set to F3, pin feed structure 2
It is possible to prevent the paper 1 from lifting up or tearing, and to eliminate the occurrence of paper jams.

In each of the above embodiments, the pin roller 10 and the veri roller 1 are
A load limiting means consisting of a rotating friction surface 14 is provided between the double rollers consisting of the rollers 3 and 3. The mechanism that causes slippage when a load equal to or greater than a predetermined load F3, which is smaller than the holding force F2 with respect to the pin 11, occurs is the mechanism described above if it is on the paper feeding force transmission path from the drive source such as the paper feeding motor to the pin 11. It can be provided at any suitable position other than the position in each embodiment.

FIG. 4 shows an embodiment in which a load limiting means is provided in the middle of a reduction gear train between a drive source (motor) and a pin feed shaft.

In the fourth WJ, a drive gear 16 is provided on the output shaft of a paper feed motor (drive source) 15 installed in the recording device.
The drive gear meshes with a drive-side friction gear 18 that is pivotally supported by a friction gear shaft 17. A driven side friction gear 19 is rotatably supported on the friction gear shaft 17, and a friction engagement surface 20 for transmitting rotational force by friction is provided on opposing sides of each of the drive side and driven side friction gears 18 and 19 on the same axis. It is provided. This frictional engagement surface is a surface that generates a predetermined frictional holding force (corresponding to the holding force F3 in FIGS. 1 and 3) by pressing the drive side friction gear 18 with the spring 21. For example, one side Alternatively, both surfaces are formed of a lining material having a predetermined friction such as felt material or sintered material.

The driven side friction gear 19 meshes with a feed gear 22 fixed to the pin feed shaft 9.

In this case, the pin roller 10 can be configured to rotate integrally with the pin feed shaft 9.

In this embodiment as well, when the frictional engagement surface 2o reaches a predetermined load F3 which is greater than the normal tension T1 of the paper l and smaller than the holding force between the feed hole of the paper 1 and the pin 11, slipping is prevented. Therefore, the same operation and effect as in the case of FIG. 1 or FIG. 3 can be achieved.

FIG. 5 shows the flat frictional engagement surface 2 in the embodiment of FIG.
An embodiment of the pond is shown in which a tooth profile engagement surface 23 is provided instead of 0, which causes slippage by running over the inclined tooth surface and causing tooth skipping when the transmitted rotational force increases to a predetermined value or more.

The other parts of the configuration in FIG. 5 are substantially the same as those in FIG. 4, and corresponding parts are indicated by the same reference numerals, and detailed explanation thereof will be omitted.

In this embodiment as well, by selecting the pressing force of the spring 21, the inclination angle of the tooth profile, the friction coefficient of the engagement surface, etc., it is possible to achieve the same effect as the rotating friction surface 14 of FIG. 1 or 3. Load limiting means can be formed.

In each of the illustrated embodiments, the pin feed structure is of a type in which paper is fed by a pin roller (feed roller) 10, but the present invention is a pin feed structure of a type in which paper is fed by a belt type pin tractor (feed tractor). The same can be applied to

Further, the present invention can be implemented in any recording device that prints on continuous paper (fan-hold paper) having feed holes, regardless of the type of print head, such as a thermal head, wire dot head, or inkjet head. It can be implemented regardless of the type of recording device, such as a printer, facsimile, or typewriter.

〔effect〕

As is clear from the above description, according to the present invention, even when the frictional force between the paper and the platen roller becomes excessive,
It is possible to obtain a pin feed structure for a recording device that can prevent paper from lifting or tearing and can eliminate the occurrence of paper jams.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a recording device equipped with a pin feed structure according to an embodiment of the present invention, and FIG. 2 is a line 1 shown in FIG.
3 is a cross-sectional view of the main part of a tension-type recording device in which the pin feed structure of FIG. 1 is arranged on the exit side from the printing position, and FIG. 7 is a schematic plan view showing main parts of pin feed structures according to other embodiments of the present invention. 1.--Paper, 2-..-Pin feed structure, 10
・・・-One pin roller (feed roller), 1・---m
-・Pin, 13-...-Slip roller, 14-・-・
Rotating friction surface, 20--Friction engagement surface, 21--...
-Spring, 23----tooth engagement surface, T1--
---Paper tension, Fl---Frictional force of platen roller, F2---Holding force between pin and feed hole, F3--
−・・−Maximum rotational transmission force. Agent Patent Attorney Yasushi Ooto Figure 1 Figure 4 Figure 5

Claims (1)

[Claims] (1) In the pin-feed structure of a recording device that feeds paper by hooking a pin into a paper feed hole, there is a tension in the paper feed force transmission path from the drive source to the pin that is greater than the normal paper tension and A pin feed structure characterized by being provided with a load limiting means that causes slippage when a predetermined load smaller than the holding force between the hole and the pin is reached.