JPH0631999A - Form guide apparatus for printer - Google Patents

Abstract

PURPOSE:To provide a form guide apparatus for a printer capable of accurately cuing a cutform inserted into a cutform-feed path. CONSTITUTION:A cutform-feed path 12 extended toward the contacting sections of a platen 2 and a pinch roller 6 is installed, the front end of a cutform 11 is brought into contact with the platen 2 when the cutform 11 is inserted into the cutform-feed path 12, and a paper guide 14 separated from the platen 2 is mounted near the front end of the cutform-feed path 12 in a dislaceable manner when the platen 2 is rotated. A form sensor 28 detecting the cutform 11 passing through the paper guide 14 is set up, and a projection 29 arranged within a range from the contacting sections of the platen 2 and the pinch roller 6 to the form sensor 28 and projected to the platen 2 side is formed to the paper guide 14. The position of the front end of the cutform 11 inserted into the cutform-feed path 12 is positioned accurately by the projection 29, and the cutform 11 is cued.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper guide device for a printer.

[0002]

2. Description of the Related Art Conventionally, a cut sheet feeding path extending toward a contact portion between a platen and a pinch roller is provided, and a paper guide is movably provided near the tip of the cut sheet feeding path. A sheet sensor for detecting the cut sheet passing through the guide is provided, and when the cut sheet is inserted into the cut sheet feeding path, the leading edge of the paper guide is brought into contact with the platen so that the cut sheet is inserted into the cut sheet feeding path. Position the tip of the cut sheet near the contact area between the platen and the pinch roller and stop it.After that, move the paper guide away from the platen and drive the platen in this state to convey the cut sheet. There is a printer that performs so-called cueing by which the platen is driven until the leading edge of the sheet reaches the front of the print head by determining the drive time of the platen based on the detection signal of the sheet sensor that detects the passage of the sheet. .

That is, since the single-cut sheet cannot be conveyed unless the single-cut sheet is inserted to the contact portion between the platen and the pinch roller, when the single-cut sheet is set on the platen, the tip of the paper guide contacts the platen. Then, the front end of the paper guide receives and positions the front end of the cut sheet. When the single-cut sheet is conveyed thereafter, the paper guide is moved away from the platen to reduce the resistance against the single-cut sheet, and to prevent the occurrence of jam even when the single-cut sheet is multiple sheets. Designed as a structure.

[0004]

When the cut sheet is manually inserted into the cut sheet feeding path, the pushing force of the cut sheet may be large depending on the user. In such a case, since the surface of the paper guide is along the outer peripheral surface of the platen, the tip of the cut sheet may reach the paper sensor beyond the contact portion between the platen and the paper guide. Such a phenomenon is more prominent as the thickness of the cut sheet is thicker or the rigidity of the cut sheet is stronger. As described above, if the sheet sensor detects a single-cut sheet when the single-sheet is inserted in a state where the platen is not driven, the program for finding the single-cut sheet is not executed, and other undesired operations are executed. The other operation is, for example, an operation in which a single cut is simply ejected.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a single-sheet feeding path extending toward a contact portion between a platen and a pinch roller, which are driven to rotate, is provided. A paper guide whose tip is in contact with the platen when it is inserted and is separated from the platen when the platen is rotated is displaceably provided near the tip of the cut sheet feeding path to detect the cut sheet passing through the paper guide. Is provided, and the paper guide is provided with a protrusion that is arranged in a range from a contact portion between the platen and the pinch roller to the paper sensor and projects toward the platen.

[0006]

The function of the platen and the pinch roller can be improved even if the user pushes the cut sheet strongly by bringing the tip of the cut sheet inserted from the cut sheet feeding path into contact with the protrusion formed on the paper guide. The leading edge of the cut sheet can be positioned within the range from the contact portion to the paper sensor. Therefore, when driving the platen after separating the paper guide from the platen,
By controlling the rotation operation of the platen based on the detection signal of the paper sensor that detects the passage of the single-cut sheet, it is possible to accurately find the top of the single-cut sheet.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Reference numeral 1 denotes a printer casing, and a platen 2 is provided in the casing 1.
Is rotatably provided, and the print head 3 is mounted on a carrier (not shown) that is reciprocally driven along the platen 2. A paper pan 4 is provided below the platen 2, and a roller holder 7 that rotatably holds a plurality of pinch rollers 5 and 6 is provided inside the paper pan 4.

Next, a continuous paper feed path 10 for guiding the continuous paper 9 conveyed from the tractor 8 toward the outer periphery of the lower part of the platen 2 is provided substantially horizontally, and the cut sheet 11 is directed to the outer periphery of the platen 2. A single-sheet feeding path 12 is provided to guide the user. This cut sheet feeding path 12 is the continuous paper feeding path 10
It has a sheet 12a that is inclined with respect to and hangs down. The sheet 12a is formed of a film of elastic polyester or the like, and the upper portion thereof is fixed to the back surface of the guide plate 13 into which the single-cut sheet 11 is introduced.

Further, a paper guide 14 is provided in a triangular space near the intersection of the continuous paper feed path 10 and the cut sheet feed path 12 so as to rotate about a support shaft 15. . The paper guide 14 has two arc-shaped ribs 16 that are fitted to the support shaft 15 so as to face each other, a first guide surface 17 that faces the continuous paper feed path 10, and an outer peripheral surface of the platen 2. The second guide surface 18 facing the front and the metal plate 1 for reinforcement
9 and. Further, the paper guide 14 is biased clockwise by its own weight about the support shaft 15, but in the usage mode in which the continuous paper 9 is used, as shown in FIG. The contact between the end portion and the stopper 20 causes the stopper 20 to stop at a fixed position. The stopper 20 is fixedly provided, for example, on the outer periphery of the support shaft 15 that does not rotate or on the frame in the housing 1.

Next, a contact / separation portion 21 for contacting / separating the roller holder 7 with respect to the platen 2 is provided.
The contacting / separating portion 21 is composed of a leaf spring 23, one end of which is connected to the roller holder 7 and the other end of which is held by a column 22, and a cam 24 which supports an intermediate portion of the leaf spring 23. The cam 24 is connected to the operating lever 25.

Further, the roller holder 7 is integrally formed with a pressing portion 26 facing the end of the paper guide 14 on the side opposite to the platen 2. Further, a paper discharge roller 27 that is driven in the clockwise direction is provided above the platen 2. The paper discharge roller 27 is provided in contact with a paper guide surface (not shown) formed on the inner surface of the cover of the housing 1, and the cut sheet 1 sent from the platen 2
1 or the continuous paper 9 is discharged.

Further, a paper sensor 28 for detecting the cut sheet 11 passing through the paper guide 14 is provided outside the platen 2. Then, the platen 2
From the contact portion between the pinch roller 6 and the paper sensor 2
8 is formed at the tip of the second guide surface 18 of the paper guide 14 so as to be arranged in the range up to 8 and project toward the platen 2 side. As shown in FIG. 3, the paper guide 14 has a plurality of ribs 30 formed on its upper surface in order to reduce resistance to the cut sheet 11.
The protrusion 29 is formed at the tip of the rib 30 on the inner side.

When printing is performed using the continuous paper 9 with such a configuration, as shown in FIG.
5 is located at the tractor feed position A. In this state, the pressure of the cam 24 against the leaf spring 23 is small, and the roller holder 7 is separated from the platen 2 together with the pinch rollers 5 and 6. In this state, since the pressing portion 26 is retracted downward, the paper guide 14 has the arc-shaped rib 16 as the stopper 2.
It rotates clockwise by its own weight until it contacts 0, and the first guide surface 17 faces the continuous paper feeding path 10 with an appropriate gap. In this state, the second guide surface 18 approaches the platen 2 and the protrusion 29 contacts the platen 2. That is, the continuous paper feeding path 10 is opened and the single-cut sheet feeding path 12 is closed. Then, by driving the tractor 8,
The continuous paper 9 is guided from the continuous paper feed path 10 to the outer periphery of the platen 2.

When printing using the single-cut sheet 11, first,
First, as shown in FIG. 1, with the pinch rollers 5 and 6 separated from the platen 2, the cut sheet 11 is fed into the cut sheet feeding path 1
Insert into 2 by hand. At this time, the user cuts 11
Even if the pushing force of the
9 is abutted. Then, as shown in FIG. 2, the operation lever 25 is rotated to the friction feed position B. As a result, the cam 24 interlocks and presses the leaf spring 23,
The roller holder 7 is pushed up, and the pinch rollers 5 and 6 are pressed against the platen 2. At this time, the paper guide 14 is pushed up by the pressing portion 26 and rotates counterclockwise about the support shaft 15 so that the second guide surface 18 faces the outer peripheral surface of the platen 2 with an optimum gap. At this time, the protrusion 29 is also separated from the platen 2. In this state, by driving the platen 2 in the clockwise direction, the single-cut sheet 11 is conveyed toward the print head 3. At this time, based on the detection signal of the paper sensor 28 that detects the passage of the single-cut sheet 11, By controlling the rotation operation of the platen 2, it is possible to accurately perform the cueing of the single-cut sheet.

Further, as described above, one operating lever 2
By operating 5, the pinch roller 5 for the platen 2,
Since the contact and separation of 6 and the switching of the paper guide 14 can be performed, it is not necessary to separately provide a switching mechanism for rotating the paper guide 14, and therefore, the number of parts can be reduced and the assembling work and the operation can be performed. It is possible to simplify the property. However, in the present invention, the paper guide 14 may be displaced manually or independently by power. Further, the tractor 8 and the continuous paper feeding path 10 do not necessarily have to be provided. Further, when the distance between the pinch roller 6 and the print head 3 is short, the pinch roller 5 can be omitted.

[0016]

As described above, according to the present invention, since the paper guide is formed with the projections which are arranged in the range from the contact portion between the platen and the pinch roller to the paper sensor and project toward the platen, the single-sheet feeding is performed. By abutting the tip of the cut sheet inserted from the path with the protrusion formed on the paper guide, even if the pushing force of the cut sheet is strong by the user, from the contact part between the platen and pinch roller to the paper sensor. The leading edge of the sheet can be positioned within the range, so when the sheet guide is moved away from the platen and the platen is driven after that, the platen rotation operation is based on the detection signal of the sheet sensor that detects the passage of the sheet. By controlling, there is an effect that it is possible to accurately find the beginning of a single-cut sheet.

[Brief description of drawings]

FIG. 1 is a side view showing a state in which a paper guide is separated from a platen according to an embodiment of the present invention.

FIG. 2 is a side view showing a state where the paper guide is in contact with a platen.

FIG. 3 is a perspective view of the paper guide.

[Explanation of symbols]

 2 Platen 6 Pinch roller 11 Single sheet 12 Single sheet feeding path 14 Paper guide 28 Paper sensor 29 Protrusion

Claims (1)

[Claims] 1. A cut sheet feeding path extending toward a contact portion between a platen driven to rotate and a pinch roller is provided, and when a cut sheet is inserted into this cut sheet feeding path, a front end of the cut sheet feeds the platen. A paper guide, which comes into contact with and separates from the platen when the platen is rotated, is displaceably provided near the tip of the cut sheet feeding path, and a paper sensor for detecting the cut sheet passing through the paper guide is provided. A paper guide device for a printer, characterized in that a projection that is arranged in a range from a contact portion between the pinch roller and the pinch roller and that protrudes toward the platen is formed in the paper guide.