JPH01241468A - Paper feeding device - Google Patents

Abstract

PURPOSE:To prevent the deformation or damage of feed holes of continuous paper and to prevent the slippage of the continuous paper off a tractor, by detecting the width of the continuous paper by means of a paper-width detector and by driving a drive mechanism in accordance with a detection signal. CONSTITUTION:When a paper-width detector 16 is positioned on a straight line 33 passing through the center of feed holes 32 formed on the opposite sides of continuous paper 31, a feed roller 13 is once stopped. In the meantime, the paper-width detector 16 is moved to the right together with a sensor carrier 17. When a home position detector 22 detects the sensor carrier 17 reaching the right end, the direction of rotation of a motor 19 is reversed and the sensor carrier 17 is moved leftward. A detecting time of this paper-width detector 16 is in accord with the width of the continuous paper 31 or the center distance of the right and left feed holes 32. These data are stored in RAM. The feed roller 13 is driven again, subsequently, a rotational angle of a tractor motor 28 is made to correspond to the data in the RAM, i.e. the width of the continuous paper 31, and an interval of a tractor 24 is made to accord with the width of the continuous paper 31.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to a paper feed device used in a printing machine.

2. Description of the Related Art Conventionally, there has been a paper feeding device equipped with a pair of left and right tractors each having a rotating body with a plurality of bins protruding from its outer periphery.

Problems to be Solved by the Invention In such a device, a tractor bin is engaged with feed holes formed at equal pitches on both sides of continuous paper, but continuous paper has different paper widths depending on the type. For this reason, the tractor is manually moved left and right each time the width of continuous paper changes, but the position of the tractor is determined only by the user's sense. The position is different, and the center of the tractor bin is shifted from the center of the feed hole of the continuous paper, even if it is slightly.

As a result, the feed hole of the continuous paper may be deformed or damaged by the tractor bottle, or the continuous paper may become damaged due to the difference in load due to the uneven engagement between the left and right feed holes of the continuous paper and the left and right tractors. One side snakes off the tractor, causing a jamming problem.

Means for Solving the Problems The present invention provides a paper feed device in which a pair of left and right tractors are provided in the path of continuous paper passing through a printing section so as to be slidable in the width direction of the continuous paper. A paper width detector for detecting the width of the continuous paper is provided in the paper width detector located upstream of the tractor, and a drive mechanism is provided for moving the tractor in the width direction of the continuous paper based on a detection signal from the paper width detector. It is characterized by

Operation: Therefore, when the continuous paper is passed through the printing section, the paper width is detected by the paper width detector. Subsequently, the drive mechanism is driven in accordance with the detection signal from the paper width detector, and the tractors are moved so that the interval between the tractors matches the paper width of the continuous paper.

Example An embodiment of the present invention will be described based on the drawings.

l is a printing section. This printing section 1 consists of a horizontally long printing stand 2 and a dot printer head 3. The carrier 4 on which the dot printer head 3 is mounted is slidably held by a carrier shaft 5 and a carrier guide 6, which are installed parallel to the marking stand 2.

Furthermore, guide stands 7 and 8 are fixed to the front and rear of the marking stand 2, which are located on the same surface as the surface of the marking stand 2.

Furthermore, between the dot printer head 3 and the marking stand 2,
An ink ribbon 10 pulled out from a ribbon cassette 9 is passed through. Further, the guide stand 7 on the upstream side of the mark stand 2 is formed with an elongated transparent section 11 parallel to the mark stand 2, and a paper guide plate 12 is attached to the guide stand 7 so as to be adjustable in the left and right directions. Further, a feed roller 13 driven by a motor (not shown) and a presser roller 14b held by a pair of left and right swinging arms 15 are opposed to each other with the guide table 7 in between, and are arranged below the guide table 8 on the downstream side. A feed roller (not shown) similar to the feed roller 13 is also provided, and a suppression roller 13b that resiliently contacts this feed roller is rotatably provided. Further, a sensor carrier 17 holding a paper width detector 16 formed by a reflective photoelectric conversion element
is slidably fitted onto the shaft 18 so as to move along the transparent portion 11 . A pair of left and right pulleys 20, one of which is driven by a motor 19 that can freely rotate in forward and reverse directions, is provided, and a portion of a belt 21 wound around these pulleys 20 is fixed to the sensor carrier 17. Further, a home position detector 22 is attached near the motor 19 to interfere with the sensor carrier 17 and detect the home position of the sensor carrier 17.

Next, on the downstream side of the guide table 8, there is a drive shaft 23 having a square cross section.
A pair of left and right tractors 24 are provided. These tractors 24 include holders 25 that slide along the drive shaft 23, a belt (not shown) that is held by these holders 25 and receives rotation of the drive shaft 23, and a belt that is movable on the upper surface of the holder 25. It consists of a paper presser 26 attached to.

These belts have bins arranged at equal pitches around the circumference. Thus, the holder 25 of the tractor 24 is attached to the drive shaft 2.
A drive mechanism 27 is provided for movement along the line 3.

This drive mechanism 27 includes two tractor motors 28 that can freely rotate in forward and reverse directions, and two screws 29 that are individually connected to these tractor motors 28 and rotate. One screw 29 is screwed into only one holder 25 and fitted into the other holder 25 so as to allow relative movement in the axial direction. Furthermore, home position detectors 30 are provided outside the left and right tractors 24, respectively, to interfere with the tractors 24 and detect the home positions of the tractors 24.

In such a configuration, the swinging arm 15 is gripped to move the suppression roller 14b away from the feed roller 13, and as shown in FIG. are moved to contact both side edges of the continuous paper 31, and the top of the continuous paper 31 is pressed by the pressing roller 14b. The downward movement of the swing arm 15 at this time is detected by an arm detector (not shown), and this detection signal allows the feed roller 13 to start. When the feed roller 13 is started, the continuous paper 31 is fed toward the printing section 1. As a result, the paper width detector 16 located at the center of the conveyance path detects the leading edge of the continuous paper 31. The period during which the feed roller 13 is driven from the time when this detection signal is output is when the continuous paper 31
The feed length is a as shown in FIG. That is, when the paper width detector 16 is positioned on a straight line 33 passing through the center of the feed holes 32 formed on both sides of the continuous paper 31, the feed roller 13 is temporarily stopped. During this time, motor 19
Since the belt 21 is driven in one direction, the belt 21 is pulled, and the paper width detector 16 is moved to the right together with the sensor carrier 17. When the home position detector 22 detects the sensor carrier 17 that has reached the right end, the rotation direction of the motor 19 is reversed, the sensor carrier 17 is moved from the right home position to the left, and the paper width detector 16 detects The time corresponds to the paper width of the continuous paper 31 or the center distance between the left and right feed holes 32. This data is stored in RAM (not shown).

Next, the feed roller 13 is driven again, and on the other hand, the left and right tractor motors 28 are rotated in one direction, and the left and right tractors 24 are moved outward by the rotation of the screw 29 in one direction. When the home position detector 30 that interferes with the tractor 24 outputs a detection signal, the rotation direction of the tractor motor 28 is reversed, and the rotation of the screw 29 in the other direction causes the tractor 24 to move inward with respect to the outer home position. Ru. The rotation angle of the tractor motor 28 at this time is the data in the RAM, that is, the continuous paper 3
It corresponds to a paper width of 1. Therefore, the interval between the tractors 24 is matched to the paper width of the continuous paper 31. Then, the continuous paper 31 sent by the feed roller 13 is transferred to the tractor 24.
is set to

In the above embodiment, the left and right tractors 24 are connected to the drive mechanism 27, but the - side tractor 24 may be fixed at any position and only the other side tractor 24 may be moved by the drive mechanism 27. be.

Effects of the Invention Since the present invention is configured as described above, the paper width of the continuous paper can be detected by the paper width detector, and the drive mechanism is driven in accordance with the detection signal at this time, so it is extremely easy to detect the paper width of the continuous paper. In addition, it is possible to accurately match the interval between the tractors to the paper width of the continuous paper, thereby preventing deformation and damage to the feed holes of the continuous paper, and
This has effects such as being able to prevent continuous paper from coming off the tractor.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and Fig. 1 is a perspective view showing the state before continuous paper is set with a portion cut away, and Fig. 2 is a perspective view showing the state before continuous paper is set with a portion cut away. FIG. 3 is a perspective view showing the process of doing this, and FIG. 3 is a plan view showing the leading end of the continuous paper.

Claims (1)

[Claims] Paper width detection for detecting the width of the continuous paper during the path of the continuous paper in a paper feeding device including a pair of left and right tractors slidably provided in the width direction of the continuous paper in the path of the continuous paper passing through the printing section. A paper feeding device, characterized in that the paper feeding device is provided with a drive mechanism that moves the tractor in the width direction of the continuous paper based on a detection signal from the paper width detector.