JPH0343015Y2 - - Google Patents

Description

[Detailed explanation of the idea] Technical field of invention This invention relates to a paper detection device for a printing machine.

Technical background of the invention and its problems As shown in FIG. 1, conventionally, a conveyance path 3 for conveying paper 2 toward a platen 1 is provided, and a detection arm 6 having a magnet 5 facing a reed switch 4 is connected with a spring. 7 urges it in the return direction (clockwise) and is rotatable around a hinge 8, and the paper 2 passing through the transport path 3 causes the detection arm 6 to retreat from the transport path 3, and a reed switch for paper detection is activated. 4 and when selectively attaching the paper feeder 9 to supply paper 2, the paper detection switch 11 attached to the paper ejection path 10 of the paper feeder 9
There is a device in which the switch is turned on by the paper 2 passing through the paper ejection path 10. The switches 4 and 11 are used to prevent blank printing when there is no paper 2.

However, the paper feeding device 9 is selectively attached or detached as necessary, and the paper detection switch 11 must be connected or disconnected from the power supply circuit via the connector 12 or the like each time. Therefore, handling is troublesome and the lead wire 12a may break. Furthermore, since two switches 4 and 11, a connector 12, etc. are required, the number of parts increases, resulting in an increase in cost.

Purpose of the invention This invention was developed in view of the above points, and it is possible to detect the paper feeding status of a fixed conveyance path and a selectively attached paper feeding device using a single paper detection switch. Another object of the present invention is to provide an inexpensive paper detecting device for a printing machine that does not allow paper to be fed from a fixed conveyance path when a paper feeding device is attached.

Summary of the invention This invention displaces the detection member by the paper to turn on the paper detection switch when feeding the paper through the conveyance path, and when feeding the paper using the paper feeder, the operating body attached to the paper feeder This operating body presses the detection member to turn on the paper detection switch.Therefore, only one paper detection switch is required, reducing costs.Furthermore, the paper detection switch of the paper feeder can be The paper feeding device is constructed so that the operation of attaching and detaching the paper feeding device can be carried out extremely easily.

Embodiment of the invention An embodiment of the invention will be explained based on FIGS. 2 to 4. Components that are the same as those described in FIG. 1 are designated by the same reference numerals, and description thereof will be omitted. An opening 14 is formed in the paper ejection path 10 of the paper feeding device 9, and a protrusion 15 is fixed thereto. body 18 is spring 1
It is biased in the return direction (clockwise) by pin 9 and rotatably held by pin 13. The other protrusion 17 and the chevron-shaped bent portion 20 of the detection arm 6, which is the detection member, protrude into the opening 21 formed in the conveyance path 3 and face each other. Further, locking pieces 22, 23 are provided on the conveyance path 3 and the discharge path 10, and are removably engaged with each other.
is formed.

In such a configuration, when the paper 2 is sent from the conveyance path 3 to the platen 1 as shown in FIG. Turn on a certain reed switch 4.

Further, as shown in FIG. 3, when the paper 2 is fed by the paper feeder 9, the operating body 18 rotates counterclockwise while bending the spring 19 due to the resistance of the paper 2, and the protrusion 17 causes the detection arm 6 to and turn on the reed switch 4. When there is no paper 2, both the detection arm 6 and the actuating body 18 are connected to the springs 7, 19.
The force returns to the clockwise direction and turns off the reed switch 4.

Therefore, the paper 2 is transferred to the conveyance path 3 or the paper feeder 9.
No matter which method is used for sending, only one reed switch 4 is required, and costs can be reduced. Furthermore, when attaching and detaching the paper feeder 9, there is no need to connect or disconnect the switch and the power supply circuit, so the operation is simple. Furthermore, the actuating body 18
is biased by a spring 19 to a rest position, so that when installing the paper feeder 9, the protrusion 17 of the operating body 18 can be correctly opposed to the left slope of the bent portion 20 of the detection arm 6. Furthermore, the distance between the protrusion 17 and the bent portion 20 can be kept constant by the engagement of the locking pieces 22 and 23, and the operation of the reed switch 4 can be made more accurate.

Further, as shown in FIG. 3, when the paper feed device 9 is attached and the paper 2 is inserted into the paper feed device 9, the protrusion 17 of the actuating body 18 presses the detection arm 6 as described above. However, even if the sheet 2 enters the conveyance path 3 and an attempt is made to pass the sheet 2 through the conveyance path 3, the protrusion 17 acts as a stopper, preventing the sheet 2 from passing through. Therefore, double feeding of the sheets 2 can be prevented, and erroneous operations can be prevented.

Effects of the invention Since this invention is configured as described above, the presence or absence of paper can be detected using a single paper detection switch, regardless of whether paper is fed through the conveyance path or the paper feeder, thereby reducing costs. In addition, since the paper detection switch of the paper feeding device can be omitted, the work of attaching and detaching the paper feeding device can be performed extremely easily.
When a paper feeder is installed and paper is inserted, it is not possible to insert another paper from the fixed conveyance path side, which prevents double feeding of paper and prevents erroneous operation. This has the effect of being able to prevent.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing a conventional example, Figs. 2 to 4 show an embodiment of this invention, Fig. 2 is a longitudinal side view showing the state in which paper is fed from the conveyance path, and Fig. 3 The figure is a longitudinal side view showing a state in which paper is fed from the paper feeder, and FIG. 4 is a longitudinal side view showing the state in which the paper feeder is separated from the conveyance path. 1...Platen, 2...Paper, 3...Transport path,
4...Reed switch (paper detection switch), 6
...Detection arm (detection member), 9...Paper feeder,
10... Paper discharge path, 18... Operating body.

Claims (1)

[Scope of utility model registration request] A conveyance path is provided for supplying paper toward the platen, and a detection member is displaceable by being displaced in response to resistance of the paper passing through the conveyance path and turns on a paper detection switch in a returning direction. , a paper feeding device selectively attached near the platen is provided, and the detection member is protruded into the conveyance path in response to resistance of the paper passing through the paper ejection path of the paper feeding device, and the detection member is moved toward the paper detection switch side. A paper detection device for a printing machine, characterized in that a pressing actuator is biased in the return direction and mounted so as to be freely displaceable.