JPH03205248A - Skew detecting mechanism for sheet material feeding device - Google Patents

Abstract

PURPOSE:To detect skew in simple manner by installing an actuator for attaching the right and left parts at the front edge of a sheet member on two supporting shafts which are turnable and installed before a feed roller and turning an actuator through the contact of a sheet member and detecting the turn of the shutter at the edge of the supporting shaft by a sensor. CONSTITUTION:Supporting shafts 12 and 13 which are coaxial and parallel to a feed roller 1 are installed in turnable manner before the feed roller 1, and actuators 3 and 4 are installed through a cut hole formed on a sheet guide 11 on the shafts 12 and 13. Shutters 5 and 6 are installed at the opposed edge parts of the shafts 12 and 13 so as to shield a transmission type sensor 7. When skew is generated on a sheet member 8 transported on the guide 11 by the feed roller 1, a difference is generated in the turn of the actuators 3 and 4 which are attached on the sheet member 8 and turned, and a difference in the shielding for the sensor 7 for both the shutters 5 and 6 is generated, and the passing time is increased, and skew can be detected from the time difference.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sheet material feeding device, and more particularly to a sheet material skew detection mechanism.

[Prior Art] Conventionally, the skew detection mechanism of a sheet material feeding device is as follows:
Generally, a mechanism is known in which skew is detected by arranging two or more sensors and calculating whether each sensor detects the sheet material and the time difference between the passage of the sheet material detected by each sensor. It is being

[Problems to be Solved by the Invention] The skew detection mechanism of the conventional sheet material feeding device described above requires the arrangement of two or more sensors, so the skew detection mechanism itself becomes bulky and expensive. There is a drawback.

An object of the present invention is to provide a skew detection mechanism for a sheet material feeding device that includes one sensor.

[Means for Solving the Problems] The skew detection mechanism of the sheet material feeding device of the present invention includes two support shafts that are parallel to the feed roller in front of the feed roller, one end of which is supported by a side frame, and which are coaxial with each other. and two actuators that are fixedly or rotatably supported by each support shaft and rotate around the support shafts when the front edge of the transported sheet material comes into contact with the two actuators; The same plate-like shape is fixed to the other end of each support shaft at a right angle or is integrated with an actuator rotatably supported by the support shaft so that the mounting angles are the same as each other, and rotates around the support shaft. a transmission type sensor arranged so that the light emitted from the emitter to the receiver is blocked by both shutters before both actuators hit the sheet material and rotate; and a feed roller. The control unit measures the time from the start of rotation until the light from the light projector of the transmission type sensor is received by the light receiver, and determines that there is a skew if the time exceeds a certain time.

[If a coskew occurs, one of the shutters will continue to block the light from the emitter even after a certain period of time has elapsed, so the light from the emitter will not be received by the receiver after the feed roller starts rotating.] Skew can be detected by measuring the time until the

[Embodiments] Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a skew detection mechanism of a sheet material feeding device according to an embodiment of the present invention, and FIGS. 2 and 3 are a shutter 5.
．． 6 is a side view showing state No. 6. FIG.

The foot roller 1 is driven by a motor (not shown) and conveys the sheet material in eight directions of arrows. In front of the feed roller I, parallel to the feed roller 1, two mutually coaxial support shafts 12.13 are provided, one end of which is rotatably attached to the side frame 2.10. Actuators 3.4 are fixed to each of the support shafts 12, 13 near the left and right ends of the sheet material 8.9 on the conveyance surface of the sheet material 8.9 in the conveyance direction through the notch holes of the upper sheet guide l1. , 9 hits the actuator 3.4, the actuator 3 moves in the direction of arrow B, and the actuator 4
rotates in the direction of arrow C.

Each support shaft 12.13 further includes an actuator 3.4.
A plate-shaped shutter 5.6 of the same shape is fixed perpendicularly to the other end of each support shaft 12.13 so that the mounting angles in the rotation direction relative to the support shaft 12.13 are the same. In a transmission type sensor 7 in which a light emitter and a light receiver are integrally formed, light emitted from the light emitter to the light receiver is blocked by both shutters 5.6 before both actuators 3.4 hit the sheet material and rotate. It is arranged so that Assuming the distance from the feed roller 1 to the actuator 3.4, when the sheet material is conveyed normally, the time t from the start of rotation of the feed roller 1 until the actuator 3.4 hits the sheet material is If the conveyance feed rate is V, t=β
/V. The state of the sheet material 8 shown in FIG. 1 indicates normal conveyance of the sheet material, and at this time the actuator 3.4 rotates at the same time, so that the shutter 5.6 also rotates at the same time from the state shown in FIG. The sensor 7 detects the sheet material. On the other hand, when the sheet material is conveyed in a skewed manner, for example, when the sheet material 9 is conveyed, the actuator 4 is delayed in detecting the sheet material compared to the actuator 3, so the shutter 5 is rotated in the direction of the arrow D as shown in FIG. Even after the movement of the shutter 6 is removed from the windows of the light emitter and light receiver of the sensor 7, a state in which the shutter 6 blocks the windows of the light emitter and light receiver of the sensor 7 exists for a certain period of time. As a result, when the detection of the sheet material by the sensor 7 is delayed from the time t0α obtained by adding a certain time α to the logical time t, it is determined that the sheet material is in a skewed state, and the feed roller 1 is driven. By immediately stopping the conveyance of the sheet material, it is possible to prevent accidents such as jamming. In this embodiment, the time t from when the feed roller 1 starts rotating until the light from the light emitter of the transmission type sensor 7 is received by the light receiver is measured, and if the time exceeds a certain time, the skew is detected. A control unit (shown in the figure) is provided for determining the position and stopping the driving of the foot roller l.

The degree of skew detection of the sheet material can be determined by setting the time t+a to an appropriate value through experiments. In other words, if α is set to a small value, even a small skew amount will be judged as a skew, and if α is set to a large value, it will be judged as a skew only when the skew amount is quite large. The time t+α is determined.

Although this embodiment uses a transmission type sensor in which a light emitter and a light receiver are integrally formed, a transmission type sensor in which a light emitter and a light receiver are independent may also be used.

Further, the support shafts 12 and 13 are respectively connected to the side frames 2 and 13.
On the other hand, the actuator 3 and the shutter 5, and the actuator 4 and the shutter 6 may be integrated and rotatably supported on the support shafts 12 and 13, respectively.

[Effects of the Invention] As described above, the present invention has the effect of realizing a small and inexpensive skew detection mechanism for a sheet material feeding device by using only one sensor.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a skew detection mechanism of a sheet material feeding device according to an embodiment of the present invention, and FIGS. 2 and 3 show a shutter 5,
6 is a side view showing state No. 6. FIG. l...Feet roller, 2...Side frame, 3
...Actuator, 4...Actuator, 5.
... Shutter 6... Shutter 7... Transmissive sensor, 8... Sheet material, 9... Sheet material, 10...
...Side frame, 1 1... Upper seat guide, 12... Support shaft, 1 3... Support shaft. Representative Patent Attorney Hi Uchihara

Claims (1)

[Claims] 1. In a sheet material feeding device that conveys a sheet material on a sheet conveyance path by a feed roller, in front of the feed roller, parallel to the feed roller, one end is supported by a side frame, and two coaxial A book support shaft; two actuators that are fixedly or rotatably supported by each support shaft and rotate around the support shafts when the front edges of the transported sheet material come into contact with each other near each end; A plate that is fixed at right angles to the other end of each support shaft or is integrated with an actuator that is rotatably supported by the support shaft so that the mounting angles in the rotational direction are the same, and the plate rotates around the support shaft. shutters with the same shape, and one transmissive sensor arranged so that the light emitted from the emitter to the receiver is blocked by both shutters before both actuators hit the sheet material and rotate. , a control unit that measures the time from when the feed roller starts rotating until the light from the light emitter of the transmission type sensor is received by the light receiver, and determines that there is a skew if the time exceeds a certain time. , Skew detection mechanism for sheet material feeding device.