JPH08180U - Loading sheet detection device - Google Patents

Abstract

(57) [Abstract] [Purpose] The purpose of the present invention is to measure the upper surface of the folding sheet on the paper feed table accurately and quickly, and to control the height of the paper feed table accurately and quickly. It is to provide an automatic detection device. [Structure] In order to achieve the above-mentioned object, the loading sheet of the present invention.
The detector is a reflection type photodetector in which the sensor is installed above the stacking sheet and is arranged in a straight line with respect to the through hole formed in the paper feed table where the optical axis is moved up and down. use

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a device for detecting a loading sheet stacked on a sheet feeding table of a sheet feeding device by a sensor.

[0002]

[Prior art]

 A device for detecting the stacked sheets stacked on the sheet feeding table of the sheet feeding machine by the sensor as described above has been known. However, the conventional device accurately and quickly measures the height of the upper surface of the loading sheet on the paper feeding table, and thereby maintains the upper surface of the loading sheet accurately and quickly at a predetermined value. Therefore, further improvement was required.

[0003]

[Problems to be solved by the device]

 SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned demands for conventional devices and to provide a loading sheet detection device capable of accurately and quickly detecting the upper surface of the loading sheet.

[0004]

[Means for Solving the Problems]

 The above-mentioned problem is a device for detecting a stacked sheet stacked on a sheet feeding table of a sheet feeding machine by a sensor, which is arranged above the stacked sheet and has an optical axis on the sheet feeding table. A reflective photodetector, which is arranged in a straight line with respect to the formed through-hole and outputs a first signal when the sheet disappears from the paper feed table, and a capacitive type detector which is arranged immediately above the stacked sheets. A sensor, the capacitive sensor outputs a second signal indicating a distance between the capacitive sensor and the uppermost sheet of the stacking sheet, and the paper feed tray receives the first signal. And the sheet feed table is moved upward so that it is brought to the loading position by the downward movement and is kept at a constant distance from the uppermost sheet based on the second signal. It is solved by the sheet detection device.

[0005]

[Action and effect]

 According to the detection device of the present invention, both the presence of the stacked sheets and the top sheet can be detected accurately and quickly. The reflective photodetector used to detect the presence of the sheet can clearly distinguish between two different detected conditions. As a result, the presence of the sheet can be accurately detected even if, for example, dust is floating.

Mechanical or optical sensors are not suitable for detecting the top sheet. Since the mechanical sensor is affected by wear and the like, it is not possible to accurately detect the sheet for a long period of time. An optical sensor cannot recognize the distance between this sensor and the top sheet, so accurate detection is impossible.

In view of the above, the present invention achieves the object by combining a reflective photodetector and a capacitive sensor as shown in the claims.

[0008]

【Example】

 Hereinafter, the present invention will be described with reference to the drawings. As shown in FIG. 1, the proximity sensor can recognize the last folding sheet on the sheet feeder.

The sensors B8K and B8L have a capacitive sensor and a photodetector. The photodetector is evaluated by a microprocessor controller which recognizes the last folded sheet and the capacitive sensor is used only to control the height of the loading sheet.

When paper is stacked on the bottom plate of the paper feed table, the photodetector recognizes the “paper present” state. This signal is stored by the microprocessor controller. As soon as the sheet disappears from the bottom plate, the photodetector irradiates the empty space of the hole formed in the paper feed table with light to recognize the "no paper" state. The signals are evaluated by the microprocessor controller which lowers the feeder to the lower loading position. At the same time, the signal indicating adsorption is stopped.

Loading Sheet Control Device The loading sheet control device is used to control the loading sheet in the vertical direction and has three operating methods: manual operation, half-fall (Halb Absenken) and full-fall (Voll Absenken). ) Is operated.

The operating method is selected in advance by the selection switch. Further, the loading sheet control device can perform ascending control and descending control. The above-mentioned lifting control of the loading sheet is performed by a single control device, and is used to keep a constant distance between the upper end of the loading sheet and the suction roller (Saugrad) during the folding operation. obtain. The loading sheet is driven by a triac driven condenser motor, and the loading sheet is held by a self-locking gear.

Technical requirements for a device for controlling the loading of a flat sheet The height adjustment of the loading sheet by raising and lowering the loading sheet is performed regardless of the selected operating method. This is performed based on the result of non-contact detection of the height of the upper end of the loading sheet by the capacitive sensor. This capacitive sensor serves to supply a start / stop signal (on / off control) to the drive motor which raises the loading sheet.

The initial detection signal of the sensor generated by the pre-laminated sheets is subtracted by the control electronics to establish the spacing between the fixed loading sheet and the suction cup rollers. Can be kept at

FIG. 2 shows the process of controlling the height of the loading sheet.

1 rise delay 275 ms ± 15 ms 2 rise until the sensor is covered 3 deceleration 50 ms ± 5 ms 4 Bremsimpuls 50 ms ± 5 ms When the height sensor becomes free due to the removal of the paper, The ascending delay begins (1). If the sensor is covered during the rising delay (5), the delay starts anew. After the rising delay elapses, the loading sheet moves up at a predetermined speed until the sensor is covered. Then, deceleration (3) begins with the break pulse (4). If the sensor becomes free during these times, these steps are immediately interrupted and the loading sheet rise delay and rise (6) (7) are restarted. The two seats are controlled at the same time and the loading seat is braked.

Lowering of Loading Sheet With such a function, the paper feed tray moves downward at a constant speed. As long as the paper feed tray is operated, the signal indicating suction will automatically stop, and the drive will also stop after a delay.

Manual Operation Method In the manual operation method, the loading sheet is moved by the operation of the raising and lowering functions.

In this operating method, the last sheet of the paper feed tray is recognized by the sensor in the ascending function, and then the signal instructing suction is automatically stopped and delayed. The drive also stops. Subsequently, the paper tray is lowered into an ergonomically favorable position for loading the sheets. This position is monitored by a reflective photodetector. Next, the operator stacks the sheets and places them on the paper feed tray, and the upper end of the new sheet on the paper feed tray returns to the original loading position. When the paper feed tray is at the lower position, the lowering of the loading sheet is completed, and the operator can stack the sheets arbitrarily up to the loading limit. Subsequently, by actuating the loading sheet to rise, the loading sheet is re-sent to the correct position for removal by the suction roller.

[Brief description of drawings]

FIG. 1 is a diagram showing that the last folding sheet on a sheet feeder is recognized by a proximity sensor.

FIG. 2 is a diagram showing the progress of control of the height of the loading sheet.

[Explanation of symbols]

 B8K ... Capacitive sensor, B8L ... Photodetector.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B65H 7/04 43/02 G01V 3/08 D 9406-2G 8/12

Claims (2)

[Scope of utility model registration request] 1. A device for detecting a stacked sheet stacked on a sheet feeding table of a sheet feeding machine by a sensor, the sensor being disposed above the stacked sheet and having an optical axis formed on the sheet feeding table. A reflective photodetector, which is arranged in a straight line with respect to the formed through-hole and outputs a first signal when the sheet disappears from the paper feed table; and a capacitive sensor arranged immediately above the stacked sheets. The capacitive sensor outputs a second signal indicating a distance between the capacitive sensor and the uppermost sheet of the stacked sheets, and the paper feed table moves downward when the first signal is received. Then, the sheet feed table is moved upward so as to be brought to the loading position and to keep the interval with the uppermost sheet constant based on the second signal. 2. A sheet over preparative delivery microprocessor to stop the installed suction cup roller in relation to the device, to perform the required operation in response to a signal from the reflection light detector and the capacitive sensor The stacked sheet detection device according to claim 1, wherein: